Note: Descriptions are shown in the official language in which they were submitted.
~26~?53~
BACKGROUND OF THE INVEN~ION
Our inven-tion provides volatile substance-emittinq
apparatus and methods for producing same and for using same
wherein the volatile substance can be an air freshener, stan~ard
aromati~ing materials, odor maskants, insecticides, insect
repellants, animal repellants, herbicides, pheremones and the
like. These volatile substances have previously been used
with the following delivery systems:
aerosols;
gels;
paper;
felt;
large pore polymers;
powders;
candles; and
wick-containing liquids.
With the exception of aerosols, the concentration and
rate of release of volatile substance, e.g., perfume, into the
atmosphere surrounding the container or emitting apparatus
has been a function of the rate of evaporation of volatile
material which, in turn, has been a function of the remaining
concentration of volatile material in the container or emitting
apparatus. Accordingly, the rate of mass transfer (e.g.,
diffusion in certain instances) of the volatile substance into
the surrounding atmosphere has, in the prior art, been "first
~5 oxder", that is, a function of the concentration previously
present, e.g.:
~c
d- = kc
Further~ore, with respect to the apparatus of the prior
art there has been no practical way for ascertainment by the
user as to whether or not the bulk of the volatile material
has been depleted at a particular point in time. In all in-
stances it is impossible to determine precisely when the
volatile substance is no longer being discharged in an
effective quantity andJor concentration per unit time into the
atmosphere surrounding the container. In those situations
where an aroma is being emit~ed, the actual aroma is usually
relatively powerful during the emission notwithstanding the
~20~53~
--5--
rate of emission of active agent and said aroma retains its
power even after its practical effect (e.g., air freshening)
is deminimis.
Thus, in Japanese Patent J8-0036,515 assigned to
Akane Soji K K, printings from which fra~rance is qraduallv
emitted are indicated to be p~roduced by a process comprisin~
(1) preparing fragrance-emitting ink compositions by
dispersing (a) fragrance-emitting bases prepared by mixing
perfume solutions with thermoplastic resins at eleva-ted
temperatures to homogenize the mixture, followed by cooling
the mixture to separate fine particles of gelled resin in
which the perfume is occluded in (b) a solution of film-
forming material and (2) printing the base material with
this fragrance-emitting in~ composition.
Scent-releasing polyurethane foams are shown to be
prepared in German published Application 2,945,757 (assigned
to the Tenneco Chemical, Inc.). In published Application
2,945,757, it is indicated that a ?olyurethane foam containing
a particulatefiller and perfume is prepared by first mixinq
the filler with the perfume and adding this mi~ture to a liquid
polyol and finally mixing the thus-obtained composition with
an organic polyisocyanate, water and a catalyst to produce
the resulting foam. It is indicated that the resulting
material is used as an air freshener, deodorant, perfume
sachet and the like. It is further indicated that the foam
releases the perfume at a limited and constant rate. The
said published German Application corresponds to U.S. Patent
4,226,944 issued Oll October 7, 1980.
U.S. Patent 4,247,498 issued on January 27, 1981 discloses
a method for preparing a homoaeneous microporous cellular
polymer structure which evolves perfumes, insect repellants,
odor masking agents and the like at a slow and steady rate.
The process of U.S. Patent 4,247,498 comprises (i) heating a
mixture oE a polymer which may be an olefinic polymer, con-
densation polymer, oxidation polymer or a blend thereof and a
"compatible liq~lid" to a t~mperature and for a time sufficient
~q3il~s~
--6--
to form a homogeneous solution, (ii) forming at substantially
the same time a plurality of liquid droplets of substantially
the same size in a continuous liquid polymer phase by cooli.ng
the solution, (iii) continuing cooling to solidify the polymer,
(iv) then at least partially displating the "compatible
liquid" with a perfume, an odor masking agent, an insect
repellant or the like. It is indicated at column 15, line 30
of U.S. Patent 4,247,498 that the disclosed system may be used
to create a "thin film of about 1 mil or less up to a
relatively thick block of thickness of about 2-1/3 inches".
Japanese published Application J5-5081,655 assiqned to
Kureha Chernical Industries KK discloses a slow release
air aromatizing composition which comprises an aqueous solu-
tion of water soluble high molecular weight substance of
viscosity 500-30,000 cps such as polyvinyl acetate, carboxy-
methyl cellulose, sodium al~inate, xanthan gum, etc.
admixed wi-th an oil soluble perfume or a water soluble
perfume.
Nothing in the prior art, however, discloses the novel
structure and process for preparing same of our invention
wherein a commercially viable structure capable of dispensing
at a steady state, at a visibly detectable rate either
continuously or discontinuously for discrete periods of time,
a volatile composition of matter such as a perfume, an air
freshener, an air deodorant or the like,is created.
J 5~3
--7--
OBJECTS OF ~HE INV~TION
It is an object of our invention to provide a process
for dispensing at a controllable, visibly detectable rate,
continuously or discontinuouslv for discrete and controllable
periods of time at steady state volatile compositions of
matter from a container into the atmosphere surrounding such
container.
It is a further object of our invention to provide an
apparatus useful for performing the process for controllably
dispensing at a visibly detectable rate, continuously or
discontinuously for discrete periods of time, such volatile
compositions of matter.
It is a further object of our invention -to provide â
process for dispensing at a visibly detectable rate,
controllably, continuously or discontinuously for discrete
periods of time, a perfume or air freshener or other volatile
substance from a container into the atmosphere surrounding
said container, so that when the effective volatile composition
of matter is depleted, the fact of actual depletion as well
as the rate of depletion is easily determinable by a person
~o who views the inner voi.d of t}le apparatus which is instrumental
in carrying out the process.
~ ~O~'S3(~
--8--
SUI~'L'`lAl~Y OF THE INVE~TION
Our invention defines a process for dis?ensing in a con-
trollable manner at a visibly detectable rate, continuously or
discontinuously for discrete periods of time, at steady state
("0 order"), a volatile composition of matter from a container
into the atmosphere surrounding the container and apparatus
necessary and useful for carrying out this process. The
apparatus includes a hollow totally enclosed structure co~-
prising a thin shell totally enclosin~ an inner void, the thin
shell having a base portion and an upper Dortion, said base
portion having an inner surface:
(i) at least a finite portion of the thin shell being
transparent whereby that portion of the inner void
which is located proximate to the base portion of
the totally enclosed structure is visible from
outside the -thin shell by a viewer in the presence
of visible wavelengths of white light; and
visible liaht;
(ii) contained totally with:in the inner void of the thin
shell and in place on the inner surface of the base
portion, a volatile composition temporarily
entrapped in an entrapment material and totally
entrapped in the entrapment material at least at the
instant in time of commencement of the functional
operation`of the structure (that is, when it is
removed from an air-tight pac};age); and
(iii) at least a finite section of the thin shell comprising
a microporous ?ol~mer (preferably containing a
plurality of finite solid particles) havinq a
porosity such that when the hollow totally enclosed
structure is located in an inert qas at a pressure
less than or equal to about l atmosphere, the vola--
tile material molecules (e.g., the perfume molecules
or the air freshener ~olecules) are adsorbed onto
the inner surface of the microporous polymer section
and desorbed frorn the outer surface of the micro-
porous polymer section at a constant linear veloci-ty
and at constant total derivative of concentration of
volatile substance within said thin shell with
respect to time through the rnicroporous polymer section.
s~
- 8a -
The volatile composition of another can be, in the
al-ternative, a perfume composition, a deodoran-t composition,
ar. air freshener composition, an insecticide composition, a
herbicide composition, an odor masking composition, a pheremone
composition, an animal repellant composition, or an insect
repellant composition.
The base portion of the hollow totally enclosed structure
is non-porous and transparent and the upper portion is a
microporous polymeric membrane and is opaque at least at the
instant in time of commellcement of the fullctional operation of
said structure, said base portion being sealed to said upper
portion. The upper portion preferably consists essentially
of a polyolefin intimately admixed with a powder having an average
particle diameter of from about 0.3 up to about 500 microns. The
microporous polymer can be a microporous polymeric membrane
consisting of a polyurethane foam containing a particulate filler
having an average particle diameter of from about 0.3 up to about
500 microns, said polyurethane foam formed by reacting a liquid
polyol with at ]east one organic polyisocyanate, water and at least
one ca-talyst.
More specifically, the microporous polymer can be a
3-dimensional mi~croporous cellular polymer structure comprising
a plurality oE substantially spherical microcells having an average
diameter (C) of from 0.05 to 100 microns distributed substantially
uniformly throughout the structure, adjacent cells being
interconnected by pores smaller in diame-ter than the microcells,
the pore size distribution expressed by (S) having a value in
the range of from 0.01 to 30 microns, the Naperian base log ratio
of the average cell diameter (C) to the average pore diameter (P)
having a value in the range of from 0.2 to 2.4 and the Naperian
base log ratio of the pore size distribution expressed by (S)
to the average cell diameter (C) haviny a value in the range
~6)~S3~
- Sb -
of from -1.4 -to 1.0, -the pores and the cells being void at the
instant in time of commencement of the functional operation
of said structure and the polymer being a synthetic the.remoplastic
polymer which is a polymer or copolymer of an ethylenically
unsaturated monomer, a condensation polymer, a polyphenylene
oxide or a blend thereof.
;
~Z~ 53~
g
B~IEF DESCRIP~ION OF THE DP~I~IN~,S
Figure 1 is a perspective view of a preferred e~bodiment
of the hollow totally enclosed structure of our invention,
with the material of fabrication being flexible polypro~ylene
film.
Figure 2 is an elevation view of the hollow totally
enclosed structure of Figure 1 shown in cross section with
the structure fully loaded with temporarily-entrapped
volatile substance;.
F'igure 3 is a partial cut-away plan view of the structure
of Figure 1 with the structure fully loaded with vo]atile
substance immediately prior to functional use thereof.
Figure 4 is a side view of the structure of Figure 1
shown in cross section with the volatile substance completely
spent.
Figure 5 is a perspective view of a second preferred
embodiment of the structure in accordance with our invention
with a hollow cylillder fully loaded i~mediately prior to
functional use thereof.
Figure 6 is an elevation view of the apparatus of Figure 1
shown in cross section fully loaded with volatile substance
im~ediately prior to functional use thereof, the structure
being located within an outer laraer air-tiaht structure,
the apparatus containing the entrapped volatile substance not
being in functional use.
Figure 7 is an elevation view of the cylindrical apparatus
of Figure 5 shown in cross section, with the volatile sub-
stance being fully loaded in said structure of Fiqure 5, the
structure of Figure 5 contained in a larqer enclosing cylinder
which is air-tight whereby the structure of Figure 5 is not
in functional use.
Figure ~ is an elevation view of the apparatus of Figure 5
shown in cross section with the volatile substance previously
contained in the cylindrical structure having been fully
dep]eted.
3~
--10--
Figure 9 is an elevation view of another preferred
embodiment of our invention, shown in cross section with the
volatile substance contained in the structure of our invention
being fully loaded in said structure immediately prior to
use.
Figure 10 is an elevation view of the structure of
Figure 9 shown in cross section with the entrapped volatile
substance previously contained in said structure having been
fully spent.
Figure 11 is a perspective view of a structure in accord-
ance with our invention where multiple structures (as the
individual structure of Figure 1) are connected to one-another
at locations midway between the base portions of each of said
structures and the upper portions of each of said structures
and along at least portions of the circumferential sealed edges
of each of said structures which are sealing the upper portion
of each of said structures to the base portion of each of said
structures.
Figure 1~ is an elevation view of the structure of
Figure 11 shown in cross section with each of the individ~al
structures of the inter-connected plurality of structures
being fully loaded with volatile substance immediately Drior
to functional use thereof.
Figure 13 is an elevation view of the apparatus of
Figure 11 shown in cross section with each of the inter-
connected structures of the structure of Figure 11 fully
loaded with volatile substance prior to use, the plurality
of inter-connected structures being contained in an air-tight
sealed enclosure structure which has a volume greater than the
volume of the plurality of inter-connected sealed structures.
Figure 14 is a plan view of the plurality of inter-
connected structures of Figure 11.
Figure 15 is an elevation view of the structure of
Figure 11 w~ich is actually a plurality of inter-connected
structures (as the individual structure of Fisure 1)~ with each
of the individual structures containing s?ent volatile sub-
stances immediately subsequent to the last functional use of
said structure.
~ J~S 3 ~
--11--
Figure 16 is a perspective cross-sectional view of the
structure of Figure 11 rolled u~ and placed in an air-tiqht
cylindrical outer-container when not being used.
Figure 17 is a perspective view of another preferred
embodiment of our invention wherein a plurality of hollow
totally enclosed structures are laterally and detachablv inter-
connected and have a common midplane ~ith each of said
structures being connected to at least two other of said
structures at a location midway beiween the base portion of
each of said structures and the upper portion of each of said
structures and along at least a portion of the circumferential
sealed edges of each of said structures sealing said upper
portions to said base portions. In the embodiment as set
forth in Figure 17~ the shape of the individual structures
is "heart"-shaped rather than ellipsoidal in shape.
Figure 18 is a series of graphs of percent volatiles
lost versus time comparing the functional use of structures
as illustrated in Figure 1 containing temporarily-entrapped
volatilizable substance tair freshener),not containing
volatilizable substance (but replaced by ethanol, per se) and
standard commercial air fresheners of the ~rior art as
defined according to United States Letters Patent No.
4,014,501. The graphs are more particularly described in
Examples I and II, infra.
2S Fiqure 19 is a comparative graph showing percent fraqrance
loss versus time for a structure containing air freshener-
containing volatilizable substance as set forth in Fiaure 1
versus the same volatilizable substance (air freshener con-
tained in a gel) in the absence of said structure of our
invention. (The graph is more particularly described in
Example III, infra.)
Figure 20 represents a graph of rate of fragrance loss
versus time for the structure of Figure 1 for up to one month
of use.
~X~.~'SJ~S3~
-12-
Figure 21 represents an operational graph oF rate of
fragrance loss versus ti3ne for a struc-ture as shown in Figure 6
wherein the structure of our invention is removed from an
outer container for operation and then replaced in the outer
container when not in use and the outer container is resealed
when not in use. Figure 21 indicates three separate use
(followed by storage) periods for the struc-ture of Figure 6.
Figure 22 represents a graph of rate of fraqrance loss
versus time for the entire period of possible continuous use
of the structure of Figure 1 assuminq that the structure of
Figure 1 is not replaced at discrete ti.me intervals in an
enclosed air-tight outer container.
S3(~
-13-
DETAILED DESCRIPTIO~ O~ ~HE I~IVENTION
The process of our invention comprises dispensing at a
visibly detectable rate continuously (as illustrated in
Figure 20) or discontinuously for discrete periods of time
(as shown in Figure 21) at steady state a volatile composi-
tion of matter 3 from a container, e.g., as represented by
reference numeral 50n in Figure 1 into the atmosphere
surrounding said container. The steps of this process are
examplified using structure 500 as follows:
(a) entrap~ing a volatile composition of matter whi.ch
may be a perfume composition, an air fresheninq
composition, a deodorizing composition an animal
repellant composition, an insect repellant com~osi-
tion, an insecticide, a herbicide or a pheremone
composition or the like in an entrapment agent
whereby a temporarily entrap?ed volatile composition
3 is formed;
(b) providing a first thin shell section 4 composed
of a thin polymeric shell having a curved surface
and having an inner void portion, an inner surface
and an outer surface and having a first sealable
continuous circumferential edge and a first
geometric configuration;
(c) placing the entrapped volatile composition 3 in the
inner void portion of the first thi-~ shell section
and onto the inner surface of the first thin shell
section 4;
(d) providing a second thin shell section 2 having a
second sealable circumferential edge and a shape
and volume which are such that when said second
. circumferential edge is placed in conforming adjacent
edgewise contact with said first sealable circumfer-
ential edge, a totally enclosed shell structure 500 is
produced wi.th said entrapped volatile composition 3
being totally enclosed within said shell structure
leaving a void 6 bet~Jeen sai.d second thin shell
section 2 and said volatile substance 3;
(e) placing said second thin shell section 2 havinq a
second sealable continuous circumferential edge
which substantially conforms in shape to said first
sealable circumferential edge onto said first thin
:~2~53g3
-14-
shell section 4 whereby said ~irst sealable edge
is in closely fitting sealable proximi~y with said
second sealable edge at location l;
(~) sealing said first sealable edge to said second
sealable edge at location 1 whereby the resultan~
shell structure enclosing said volatile composition 3
is air-tight except for mass transport of volatile
substance through the polymer wall (by adsorption
therefrom from void 6 and desorption therefrom into
the surrounding atmosphere) with at least a finite
section of preferably the second thin shell section
being a microporous polymer having a porosity such
that when the hollow totally enclosed structure, now
sealed, 500, is located in an inert gas at a
pressure of less than or e~ual to about 1 atmosphere,
said volatile material molecules diffuse at a con-
stant linear velocity and at a constant total
derivative of concentration of volatile substance
with respect to time throuqh said micronorous polymer
section;
(g) optionally, at time intervals of non-use, or for
storage purposes, placing the entire shell structure
500 into an outer container 7 which may or may not
be transparent and sealing the opening of the outer
container at 8 whereby the outer contai.ner 7 is
air-ti~ht.
The outer container 7 prevents the escape of the volatile sub-
stance from the entrapment medium into the atmosphere prior to
the desired operation of the shel.l structure and during
storage thereof. The outer container 7 has a volume greater
than the shell structure which is the functional portion of
the apparatus of our invention. The outer container may or
may not be transparent or it may be ?artially transparent.
Examples of the aforesaid microporous polymer compositions
of matter are as follows:
(a) ~icroporous polymers prepared, for example, according
to Canadian Patents 1,021,916 or 1,039,911 and U.K.
Patent 1,414,785 manufactured by ~oninklijke
Emballaae Industrie Van Leer B.V. of Amstelveen,
~2~ $3(~
The Netherlands, or example, disclosing a m.icroporous
film containing talc having the following specifications:
Composition Polypropylene + filler
Thickness 100 + micrometers
Weight _ 9O g/m2
Ultimate tensile 30 MN/m2 (machine direction)
strength 11 MN/m (transverse cirection)
Elongation at break 180% (machine direction)
350% (transverse direction)
Pore size 0.2 micrometers (max)
Void volume .34 cm3/g (30~)
Density - 900 kg/m
Air flow 3 cm /cm2/min at 1 kg/cm2
Water flow 0.001 cm3/cm2/min at 1 kg/cm2
Air resistance (Gurley) 104 secs.
Water vapour trans- 150 g/m2/24 hrs at 23C
mission 50-~ rh
Thermal stability 10 hrs at 130 C;
(b) Thin microporous films produced fxom Surlyn resin
as described in Examples 362, 363, 364, 365 and 366
at columns 45 and 46 of United States Patent 4,247,498;
(c) A microporous polymer membrane produced according
to Example 10 of U.S. Patent 4,226,944 which is a
polyurethane resin containing a particulate filler
except that the fragrance set forth therein is not
initially (prior to functional use) contained in
the microporous polymer shell, but is only initially
(prior to functional use) contained in the porous
retention entrapping sponge or gel 3 in Figure 2;
or 11 in Figure 5; or 19 in Figure 9;
: .
3~
15.1
(c-bis) A microporous polymer prepared according to
United States Patent 4,429,714, the abstract
for which is set forth below:
UNIW* D16 01549 D/02*~S4239-714
Modi~fying pore size distribution of microporous sepn.
medium - by immobilising a pore blocking agent of
known molecular size in the pores
UNIV OF WA~HINGTON 15.11.78 US-960745
A96 JOl (16.12.80) B29d-27
15.11.78 as 960745 (6ppl302)
The pore size distribution of a microporous sepn
medium (I) is modified by filling its pores with a
volatile liq. A controlled amt of the volatile
liq is evaporated to lower the level of the liq within
the pores to below the bulk surface of (I) and
thereby form voids at the entrances to the pores.
A conc. soln of a pore blocking agen-t is applied to the
bu]k suriace oE (I). The pore blocking acJent is
insoluble in the volatile liq and capable of being
insolubilised in its soln. Its molecular size
distribution has a predetermined lower limit so that
it only enters pores larger than that. Excess pore
blocking agent is removed from the surface of (I)
that which remains is insolubiulised to immobilise
it in the pores.
The pore blocking agent obstructs the entrances to
all pores larger than a certain size so that (I)
has a sharp cut-off in the max molecular size it
passes. (I) can be a polymeric membrane or chromatographic
gel used to separate proteins, enzymes, viruses and
immunological active fragments by ultrafiltration,
dialysis, e]ec-trodialys;s, electrophoresis or gel
perrneation or gel exclusion chromatography.
S3~
(d) A membrane produced according to Japanese A~plication
J5-5081,655 assigned to Kureha Chemical Industries KK
and published on June 19, 1980, containing a water
soluble polyvinyl alcohol having a molecular weight
of 12,000, intimately admixed with xanthan gum,
the ratio of polyvinyl alcohol:xanthan gum being
6:4 (weight:weight);
(e) A cyclodextrin microporous film containing activated
silicate as prepared according to Japanese published
Application J5-5078,965 assisned to Kokando KK and
published on June 14, 1980;
(f) A microporous polyurethane specifically as described
in German Offenlegunysschrift 2,324,31~ published
on November 29, 1973 and assigned to Teijin Cordlev
Ltd. (abstracted in Chem. Abstracts Volume 81, 1974
at section 45~9u).
Insofar as the microporous film is concerned, it is
preferred that a filler bè incorporated therein havina an
average particle size of from about 0.3 Up to about 500 microns.
In the event that a filler is not contained, the pore size
of the microporous polymer must be smaller than if a filler
is contained by 3 or 4 orders.
Particulate or pulverulent fillers which are useful in
the practice of this invention include, but are not limited
to, clays, including both untreated clays and those which
have been surface-treated in various ways well known in the
art, ground limestone, talc, precipitated calcium carbonate,
including surface-treated types, alumina, aluminium silicate,
barytes, wollastonite or other calcium silicate, silica,
zirconia, titanium dioxide, soap and synthetic detergents in
solid form.
The synthetic detergent can be, for example, an alkylaryl
sulphonate detergent, such as a sodium alkyl benzene sulphonate
ox sodium alkyl naphthalene sulphonate. ~here the sulphonate
used is an alk~l benzene sulphonate, the benzene ring of the
sulphonate referably has only 1 allyl substituent and such
substituent contains from 8 to 18 carbon atoms. Among such
alkyl benzene sulphonates are sodium linear dodecylbenzene
~2~)~53~3
-17-
sulphonate, sodiu~ tridecylbenzene sulphonate and sodium
nonylbenzene sulphonate. On the other hand, where the sul-
phonate used is an alkyl naphthalene sulphonate, the naphthalene
ring of the sulphonate preferably has 1 or 2 alkyl substituents
and the total number of carbon atoms in the alkyl substituents
is from 3 to 10. Among such sulphonates are sodium monoiso-
propylnaphthalene sulphonate, sodium diisopropylnaphthalene
sulphonate, sodium diamylnaphthalene sulphonate and sodium
monocaprylnaphthalene sulphonate. The sulphonates in solid
form are commercially available in 40~ to 90~ by weiaht active
; form, the rest being predominantly sodium sulphate. In
practicing the present invention, it is preferable to use the
90~ active form, which is the highest available com~lercially,
but other formscan also be used.
Useful clay fillers are described in U.S. Letters Patent
3,080,256 and are compositions which can be prepared by a
procedure involving coating kaolin with a small amount ~for
example, from 0.2% to 2~ by weight, based on the weight of
the kaolin) of a polyamine, e.g. ethylene diamine, hexamethyl-
ene diamine/ tetraethylene diamine, diethylene triamine,
tetraethylene pentamine and guanidine.
Other useful clay fillers are describea in U.S. Letters
Patent 3,151,993 and can be prepared by a procedure involving
coating kaolinite particles with aluminum hydroxide precipitated
in situ at a pH from 7.5 to 9. We prefer to use clay,
limestone, soap, linear dodecylbenzene sodium sulphonate,
combinations of clay and linear dodecylbenzene sodium sul-
phonate, or combinations of clay and soap. Other particulate
or pulverulent fillers can also be used. The only limitations
are that the fillers should not adversely affect or react
with the aromatizing substance or entrapping material entra~pinq
the aromatizing substance used or absorb the aromatizina
material to such a degree that release from the microporous
polymer is unduly inhibited or entirely prevented. Although
the particle size of the filler can be varied over a wide
range, 0.3 microns up to 500 microns, extremely coarse particles
are generally undesirable because they may detract from the
aesthetic qualities of the finished microporous polymer.
530
-18-
The amount of filler can be varied over a wide range
depending on the amount of volatilizing material to be released
from entrapped volatilizable substance 3 and the viscosity of
the aromatization material which is adsorbed onto and desorbed
from the microporous polymer. We have found that filler
levels in a range of from S to 100 parts by weight per 100
parts of polymer are generally satisfactory, although greater
or less amounts can be used if desired.
Any type of aromatizing substance, e.g., air freshener,
can be used in the practice of this invention provided that
it does not react with any component of the microoorous
polymer or polymer or other substance used ln fabricating the
outer shell of the structure of our invention. Fragrances
are usually c~mplex mixtures and no component of the desired
fragrance should be reactive with any component of the
microporous polymer or any other component which is used to
fabricate the shell structure of our invention.
Insofar as the microporous film produced in accordance
with United States Patent 4,247,498 is concerned, this
microporous film is produced by heating a mixture of synthetic
thermoplastic polymer which may be a polymer or a copolymer-of an
ethylenically unsaturated monomer, condensation polymer, poly-
phenylene oxide or a blend thereof and a compatible liquid to
a temperature and for a time sufficient to form a homogeneous
solution; allowing the solution to assume a desired shape
(in this case, film or thin shell polymer) and cooling the
solution to initiate liquid-li~uid phase separation and foxm at
substantially the same time a plurality of liquid droplets of
substantially the same size in the continuous liquid polymer
phase, continuing the cooling to solidify the polymeric film
and removing substantially all of the liquid resulting to form
a polymer structure which is a three-dimensional microporous
cellular structure comprising a plurality of substantially
spherical microcells having an average diameter (C) from about
0.05 to about 100 microns ~more preferably 0.05 to 15 microns)
distributed substantially uniformly throughout the structure,
adjacent cells being interconnected by pores smaller in
diameter than the microcells, the pore size distribution
expressed by S having a value in the range of from 0.01 to 30
microns, the log ratio ~Naoerian base) of the average cell
~oa~s3~
--19--
diameter (C) to the average ?ore diameter (P) having a value
in the range of from 0.2 to 2.~ and the log ratio (Naperian
base) of the pore size distribution expressed by (S) to the
average cell diameter (C) having a value in the range of
from -1.4 up to 1.0, the pores and the cells being a void and
the polymer being a synthetic thermoplastic polymer which is
a polymer or copolymer of an ethylenically unsaturated
monomer, a condensation polymer, a polyphenylene oxide or a
blend thereof. Preferably, the polvmer phase and compatible
liquid have intimately admixed therewith the aforedescribed
filler in proportion ranges stated, supra.
When the structure of our invention is ready to be used
in dispensing at a steady state, and at a visibly detectable
rate continuously or discontinuously for discrete periods of
time from container 500, the container 500 is removed from
outer container 7 and maintained in an~ convenient area or
3-space. Figure 4 illustrates the container 500 in cross
section after the entrapped volatile material is totally
depleted as a result of the steady state mass transport of the
volatile substance through microporous polYmer section of a
portion of the container wall, e.g., preferably wall_2. The
fully depleted substance is shown in Figure 4 as indicated
in reference numeral 5.
If desired, as an additional embodiment of this invention,
each of the shell structures of our invention may be inter-
connected as shown in Figures 11, 12, 13, 14, 15, 16 and 17
as structures 504,505 and 506. Thus, a plurality of hollow
totally enclosed structures, having upper portions 23A, 23B,
23C, 23D, 23E, 23F, 23G, 23H and 23J are laterally and
_ _ _ _ _
detachably interconnected,having a co~mon midplane 22A, each
of said structures being connected to at lease two other of said
structures, for example in structure 504, at a location midway
between the base portion of each of said structures and the
upper portion of each of said structures, with the base portion
and upper portion of three of said interconnected structures
shown in Figure 12, to wit: the upper portions as 23C, 23D and
23J and the lower portionsshown as 29C, 29D and 29J.
:12~ 3(~
-20-
In constructing such a structure as structure 504 in
Figures 11, 12, 13, 14, 15, 16 and 17, the upper polymeric
portion containing upper portions 23A, 23B, 23C, 23D, 23E,
23F, 23G, 23H and 23J having a sealable circumferential edge
22A is sealed to a diametrically opposed lower portion con-
taining such lower portions as 29C, 29D and 29J at sealable
circurnferential edge 22B with sealable circumferential edges
22A and 22B being in closely fitting sealable proximity with
one another whereby when they are sealed, an air-tight connection
is produced with the only means of ingress and egress from the
voids 27C, 27D and 27G for the volatile substances contained
in _6C,_6D and 26J being through microporous polymer sections
in upper shell portions 23C,_3D, 23J and the like, and/or
lower portions 29C, 29D and 29J and the like.
When such a structure as structure 504 as illustrated in
Figures 11, 12, 13, 14, and 15 are produced, they may be
stored while not in use in a container such as container 24
as illustrated in cross section in Figure 13 or they may be
rolled up and stored in container 505 as illustrated in Figure
16. Conveniently, the container 505 in Figure 16 is
cylindrical in shape and has a closure which is in the form
of a screw top which may be easily removed and replaced for
the purposes of storing structure 504 while not in use. I~hen
structure 504 is stored while not in use, the pressure within
container 505 and without structure 504 and within structure
504 is equalized so that during storage no mass transfer from
such entrapped volatile substance material as 26C, _6D and
26J takes place into the outer atmosphere.
~fter the structure 504 is removed from the outer container
such as container 24 or container 505, it is then placed in an
appropriately convenient place and the volatile substance is
depleted from such substances as 26C, 26D and 26J until such
point as the totally depleted substance is visible from
without structure 504 and is shown to be depleted as illustrated
in Figure 16 (asreference numerals 28C, 28D and 28J). Thusly,
the void 27C~ 27D and 27J is fully visible l'rom outside the
structure in the presence of the visible wavelengths of-light
(e.g., white light) so that the depleted substance 28C, 28D
and 28J whether it be a gel or microencapsulated material or
sponge material, is easily visible.
~Z(3~J~53~
-21-
Figure 17 illustrates a variation of structure 504 as
structure 506 wherein the individual structures may be
separated for individual use at 507, with the shape of the
upper portion of each of the individual structures indicated
as a "heart" shape at 50~.
Comparative operation of structure 500 with perfumed
fragrance entrapped material or ethyl alcohol entrapped
material at 3 with material 3 in prior art apparatus (e.g.,
that described in U.~. Patent 4,014,501) is set forth in
Figure 18. The graphs shown by reference numerals 201 and 203
represent the o~eration of structure 500 (percent volatile sub~
stance loss versus time) without any perfume material
contained within the entra~ped volatile substance 3 but only
containing ethyl alcohol entrapped in ~el 3. The graphs
shown by reference numerals202 and 204 (percent per~ume lost
versus time) indicate the rate of release versus time using
structure 500 when employing 2% fragrance in a gel indicated
by reference numeral 3 with the microporous polymer in
structure 500 for reference numerals 201, 202, 203 and 204
being that described in Canadian Patents 1,039,911 and 1,021,916
and U.K. Patent 1,414,785 whereby specially compounded poly-
propylene film with talc is used, having the following
specifications:
Composition Polypropylene + filler (talc~
Thickness 100 - micrometers
Weight _ 90 g/m2
Ultimate tensile strength 30 MN/m2 (machine direction)
11 MN/m2 (transverse direction~
Elongation at break 1~0% (machine direction)
350~ (transverse direction)
Pore size 0.2 ~micrometers (max)
Void volume .34 cm3/g (30
Density - 900 kg/m
Air flow 3 cm3 /cm2/min at 1 kg/cm2
Water flow 0.001 cm3/cm2/min at 1 kg/cm~
Air resistance (Gurley) 10 secs
Water vapor transmission 150 g/m2/24 hrs at 23C 50% rh
Thermal stability 10 hrs at 130C
as manufactured by Koninklijke Emballage Industrie Van Leer
B.V. o~ Amstelveen, The Netherlands.
, ~ '
53(3
-22-
In each of the graphs wherein perfurned material is used,
it is apparent that for the major portion of the useful life
of the structure, e.g., structure 500, the rate of mass
transport of perfume substance, when in use, is "0" order,
that is:
dc - k
dt
wherein k is a constant.
Discussion covering the preparation of the compositions
of matter which constitute the fragranced gels and unfragranced
gels whereby the graphs as represented by reference numerals
201, 202, 203, 204 and 205 of Figure 18 are prepared is set
forth in Examples I and II, infra.
By the same token, in Figure 19, the graph indicated by
reference numeral 302 indicates percent fragrance loss versus
time for an air freshener gel containing 2~ by weight fragrance
but not enclosed in a structure defined according to our
invention. It will be noted that the diffusion of the air
freshener is in accordance with ordinary diffusion laws and
is not steady state, to wit:
~C, I~aoc,~ l~C"~ /~C~
_ = D~ J + ~ .2 J ~+ ~
On the other hand, the graph indicated by reference
numeral 301 in Figure 19 is for the same air freshener gel 3
containing 2% by weight fragrance (as more particularly
described in Example III) located in the thin shell structure
of our invention as illustrated in Figures 1, 2 and 3. The
depleted air freshener gel is shown by reference numeral 5
in Figure 4 (the depletion being at the end of a 55 day period
as shown on the graph indicated by reference numberal 301
in Figure 19).
Figures 20 and 21 show, res~ectively, continuous and
discrete usages of the shell structure as illustrated in
~igure 1. Figure 20 is a graph of dt versus time; wherein
during the first five minutes of operation, the mass transfer
rate is described as "unsteady state" until a "steady state"
condition is reached wherein ddt is a constant for at least
one month (until de~letion as shown in Figures 4 and-8).
3V
-23-
In Fig~lre 21, dt is a constant after the first five
minutes of usa~e until the time tl-at the shell structure of our
invention as shown in Figure 1 is placed into an outer contain-
er as shown in any one of Figures 6, 7 or 16.
Fiyure 22 is a graph of dt versus time wherein the ~eriod
... ..
of from to to tl is a condition of "unsteady state" mass
transport (usually no more than a few minutes) and the
period from tl to t is a condition of "steady state" mass
transport; a very long period of time, e.g., 55-75 days and
even longer.
The "steady state" adsorption/desorption of volatile
substance mass transport mechanism onto and from the mi.cro-
porous polymer section of the shell structure of our invention
may be set forth i.n the form of a mathematical model as taught
by Adamson "Physical Chemistry of Surfaces" Second Edition,
Interscience Publishers, 1967, as follows:
n2'(appare~t)=nO~N,7
rS~ = (n'/2)(AT2'--N:~)
r2~ )tn2~/n~--Tl2'/n')
rl'= (~/2)(N,- NaT)=TIo~N~
r2 = Tlo~ 2 /~-- = (~2 N~ A 2 )/~
1 + (A--l)Ars
r2'=(n~/2) (K - I).N,AT2
1 + (~
A',N:/7-~N, = I/n'(K -- I) ~ (l/n~)Ars
2r2l = nS'--n~'(Ar2/N~) = n'(l~a'--N~'~r2/NI)
2r2~ = ~nlN~)(N2' -- N2)
rl = r2~ N2
r~ = t~ N~ l)AT2]~
0 (K - I)NINJl1 + (K - 1)N~ ~ l)NIA~J(N~ + KNI)
D = ~'N2/(ATI J~ h'~ )--N:
~(3~53~)
-24-
wherein the -terms with the superscript "s" refer to components
in the adsorbed layer and the terms with the superscript "1"
refer to terms in solution; the terms with the subscript "1"
refer to a "First" component and the terms with subscript "2"
refer to a "second" component; with "N" referring to mole
fraction and "n" referring to number of moles and with
,~
being indicative of "surface excess"; "~" being indicative
of equilibrium constant and
representing the sum total of the moles on the adsorbed layer.
Another e~bodiment which is preferred for the practice
of our invention involves the use of a rigid rather than
flexible polymer in forming rigid cylindrical containers
useful for the process of our invention as illustrated in
Figures 5, 7, 8, 9 and 10~
The process of our invention for dispensing at a control-
lable and visibly detectable rate, continuously or discontinu-
ously, for discrete periods of time a volatile composition
of matter from a cylindrical container 501 into the atmosphere
surrounding the container in this particular e~bodiment
comprises the steps of:
A. Entrapping the volatile composition of matter, e.g.,
perfume, in an entrapment agent (the entrapped material
being indicated by reference numeral 11) whereby a
temporarily entrapped volatile comPos,tion is formed;
B. Placing the entrapped volatile composition 11 within
cylinder 501 (that is, a first thin shell section
thereto). The top of the cylinder 101 and the bottom
of the cylinder 102 may be fabricated from a trans-
parent non-porous polymer (that is, a polymer which
is not porous to the volatilizable substance) whereby
the inner void of the cylinder can be viewed from the
5~3~
-~5-
outside of the container so that one can easily
ascertain when the entrapped volatile substance,
11 is depleted (as shown by reference numeral 16
in Figure 8), The side wall of the cylinder 12
may be fabricated from a microporous polymer such
as that described in Canadian Patent 1,039,911 or
United Kingdom Patent 1,~14,785 assigned to
Koninklijke ~mballage Industrie Van Leer B.V. or
can be produced of microporous polymers which are
laminated such as that described in Israel Patent
52650 assigned to Koninklijke Emballage Industrie
Van Leer B.V. wherein, for example, -the polymer is
microporous and con:tains a talc filler.
When not in use, the cylinder 501 containing entrapped
volati]e substance 11 is preferabl~ nlaced in an outer
cylindrical container 502 as shown in Figure 7. The outer
cylindrical container is referred to by reference numeral 502
in Figure 7. The outer cylindrical container has a removable
cap _ which may be screwed at 103 into the lower portion 13_ _
of said outer container 502. ~Jhen the cylinder 15 is in use,
the screw top 1~ is removed and the inner container 15
containing the entrapped volatile composition 11 may remain
in place within the outer container 502 or may be removed to
a more convenient location for use. Not all of the side wall
12 need be fabricated of microporous polymer. Indeed, merelv
the upper third or the up~er quarter or the lower quarter of
the side wall or even the top or the bottom of the cylindrical
container may be fabricated from micro~orous polymer, the
remainder of the container 15 shell being fabricated using a
transparent substance which is rigid or flexible or using a
silicate or quartz glass.
~other embodiment of the cy]indrical hollow structure
which is illustrative of our invention is set forth in
Figures 9 and 10 wherein the upper portion of the cylindrical
structure 17 may be screwed into the lower portion of the
structure 18 at screw threàds 20. Thus, structure 503
containing volatile substance 19 may be manufactured in a
form which is reusable wllen the volatile substance 19 is
depleted down to the remaining depleted gel (or other
P530
-26-
entrap~ent substance) 21 as indicated in Fisure 10. Con-
veniently, lower portion 18 may be fabricated from a trans-
parent substance such as transparent rigid polypropylene or
glass and upper portion 17 may be fabricated from microporous
polyurethane or polypropylene containing talc and may be
perpetually opaque or opaque only when cylinder 503 is not
in use. Thus, when volatile substance 19 is depleted down
to depleted substance 21 (as illustrated in Figure 10), the
upper portion 17 of cylinder 503 in Fiqures 9 and 10 may be
temporarily removed and additional substance 19 may be added
to the lower portion 18. Structure 503 in Fi~ures 9 and 10
may then be replaced into a larger cylinder to form a
structure such as that illustrated in Figure 7, the purpose
of which is for storage; until it is decided to reuse the
structure 503.
The rate of mass transport of volatile substance from
cylinder 501 or from cylinder 503 is over substantially the
entire period of presence of volatile substance in entrapment
composition, "steady state" or constant. Thus, altho~h the
general mass transport equation is:
N ~ =--D,~
~y
wherein NA is the molar rate of mass transport per unit area;
DAB is the "diffusivity" of A in B, a physical property of the
volatile vapor and the adsorbing polymer, CA is the molar
concentration of A in the void s~ace immediately within the
shell; and y is the thickness of the adsorbing and desorbing
polymer. For the purposes of our invention NA is a constant
and is not a function of time during the operation of the
hollow totally enclosed structure of our invention. Indeed,
when operating in several directions, the equation for mass
transport of volatile substance is:
~J ~( L~'- )~ ~ ( ~- )ZV~
wherein ~C{ is a constant.
a~
* * * * *
~Z(3li'530
-27-
The following examples serve to illustrate embodiments
of our invention as it is now preferred to practice it with
reference to using air freshener/perfume compositions in
conjunction with the hollow totally enclosed structures of our
invention as illustrated Figures 1, 5, and 9. It will be
understood that these examples are illustrative and that the
invention is to be restricted thereto only as defined in the
appended claims.
S30
-28-
EXAMPLE I
Into compartment 6, onto surface 4 of the structure 500
illustrated in Figures 1, 2 and 3 is placed a composition
prepared as follows: 3.0 parts by weight of Carbopol ~ 940
(manufactured by the B.F. Goodrich Company) (see Note 1) is
sifted into the vortex of rapidly stirring water (88.8 parts
by weight) containing 0.2 parts by weight of methyl ~araben. The
mixing is continued until a smooth clouay dispersion is formed.
2.0 parts by weight of a perfume co~position (see Note 2) is
~ added to the prepared slt~rry and the slurry is continued to be
mixed until the perfume composition is dispersed. The slurry
is then neutralized with 6.0 parts by weight of diisopropanol-
amine (50% solution in water) using slow mixing to avoid the
inclusion of air. The structure 500 is then sealed along
the circumferential edges at location 1 as shown in Fi~ures 1,
2 and 3 and use of the structure resulting therefrom is shown
in accordance with the graph referenced by reference numeral
202 in Fiqure 18. When instead of the perfume (Note 2), only
_
ethyl alcohol is used as the volatilizable material, the
operation of structure 500 is in accordance with the graph
indicated by reference numeral 201 in Fi~ure 18. It will be
noted that for periods of use, structure 500 operates at steady
state very soon after (5 minutes) use is commenced.
* * * * *
Note 1: Carbopol ~ 940 is ~roduced by the B.F. Goodrich
Chemical Company of 3135 Euclid Avenue, Cleveland,
Ohio. It is identified as a carboxyvinyl ?olymer of
hiqh molecular weight.
Note 2: The formulation of the fragrance is as follows:
IngredientsParts by Weight
Para cresol
~lethyl jasmonate 100
Acetyl methyl anthranilate 20
Farnesol 4
-Cis-3-hexenyl benzoate 30
Nerolidol 30
Indol 15
Eugenol 20
Benzyl alcohol 40
53(~
Ingredients Parts by Weight
Methyl linoleate 40
Jasmin lactone 20
Dihydromethyl jasmonate 10
Linalool 150
Benzyl acetate 400
Abietyl alcohol 150
Cis jasmone 150
* * * * *
, .
The evaporating surface in hollow structure 500 is
8 square inches; and the weight of entra?ped volatile
substance 3 is 30 grams.
EXAMPLE II
3.0 parts by weight of Carbopol ~ 940 (manufactured by
the ~.F. Goodrich Company) is sifted into the vortex of
44.4 parts rapidly stirring ethyl alcohol and 44.4 parts of
distilled water. Mixing is continued until a smooth, cloudy
dispersion is formed. 2.0 parts by weight of the perfume of
Example I is then added to the prepared slurry and mixing is
continued until the perfume is dispersed~ The slurry is then
neutralized with 6.0 parts by weight of diisopropanolamine
(50~ solution in water) using slow ~ixing to avoid inclusion
of air. The resulting gel is then placed into cylinder 501
of Figure 5. The use of this air freshener cylinder is in
accordance with the graph indicated by reference numeral 204
in Fiyure 18. ~ithout the use of the perfume composition of
Example I, the cylindr,ical shell of Figure 5 operates in
accordance with`the graph indicated by reference numeral 203
in Figure 18~ In both cases, the ~ercent volatiles lost during
Example I (but using ethanol, instead), the cylindrical shell
of Figure 5 operates in accordance with the graph indicated by
reference numeral 2 in Figure 18. In both cases, the
percent volatiles lost during operation of the cylinder 502
is in accordance with a steady state mass transport mechanism
can be observed from the graphs 201, 202, 203 and 204 of
Figure 18.
'53~
-30-
When the gel of this example is simply used in a commer-
cial air freshener (in the air freshener of ~.S. Patent
4,014,501), the mass transport mechanism is "unsteady state"
in accordance with the graph indicated by reference numeral
205 in Figure 18.
EX~IPLE III
83.45 qrams of distilled water is heated to 85C. With
rapid agitation on a propeller type mixer, Gelcarin ~ AFG-15
(carageenan prepared by the ~arine Colloids Corporation) is
dispersed in the water. 3.50 grams of glycerine is slowly
added to the carageenan dispersion. The mixture of glvcerine
and carageenan is then reheated and combined with 2.0 parts
by weight of the perfume composition of Example I and 8.00
parts by weight of Tween ~ 80 (a trademark of I.C.I. America)
(see Note 3). 0.05 parts by weight of formaldehyde is then
added to the resulting mixture slowly and the resulting
material is then poured into the cylinder of Figure 9. It is
material is then poured into lower portion 18 of cylinder 503
of Figure 9. The lower portion 18 of cylinder 503 is then
sealed at 20 with upper portion 17 and placed in use.
The graph indicated by reference numeral 301 indicates
the length of time of usefulness of the resulting cylinder;
a "steady state" mass transport mechanism for the use of
cylinder 503 as an air freshening apparatus.
When the composition prepared above is used in accordance
with a standard air freshener packa~e (per U.S. Patent
4,014,501),the rate of fragrance loss is shown in accordance
with the graph indicated using reference numeral 302 in Fiaure
19 (an unsteady state mass transport mechanism rather than
the steady state mass transport mechanism of graph 301 in
Figure 19).
* * * * *
Note 3: Tween ~ 80 is a mixture of oleate esters of sorbitol
and sorbitol anhydrides consisting predominantly of
12(3~530
the monoester condensed with approximately 20 moles
of ethylene oxide in accordance with the formula:
MO(CH,CM,O~ (OCIl,Ct~",OM
o ct~--loCH~Ct1~rOH R
CH,--(OCH,CH,) O--C~CM,),u1=CH(c11~.CH,
wherein w ~ x + y + z has an avera~e value of 20.
,--
~2~53~)
- 32 ~
SUPPLEMENTAR~ DISCLOSURE
It is a further object of our invention to provide
a process for dispensing at an approximately constant rate,
continuously or discontinuously for discrete and controllable
periods of time volatile compositions of matter from a container
into the atmosphere surrounding such container enabled by
the use of a polymer shell or film or sheet, monolayer, bilayer
or multilayer ("membrane") that is defined by (i) having the
property of either transporting water vapor at a rate of between
about 50 up to about 1000 g/m2/day at about 25C and at about
50~ relative humidity at about atmospheric pressure and/or
having an air transport rate of 100-20,000 Gurley seconds (Gs);
and (ii) a thickness in the range of from about 0.01 mils up
to about 20 mils.
Our invention utilizes a polymer shell or film
or sheet, monolayer, bilayer or multilayer (thereinafter referred
to as "membrane") that is defined by having (i) the property
of either water vapor at a rate of between about 50 up to about
1000 g/m2/day at about 25C and at about 50% relative humidity
at about atmospheric pressure and/or having an air transport
20 rate of 100-20,000 Gurley seconds tGs); and (ii) a thickness
in the range of from about 0.01 mils up to about 20 mils, for
enabling a process to take place for dispensing in a controllable
manner at a constant rate, continuously or discontinuously
for discrete periods of time at substantiallysteady state ("0
order") over an extended period of time a volatile composition
of matter from a container into the environment surrounding
the container. Our invention also defines an apparatus necessary
and useful for carrying out this process. The apparatus includes
a hollow totally enclosed structure comprising a thin shell
totally enclosing an inner void, the thin shell having a base
portion having an inner surface:
~-,
:~2~ 3~
- 33 -
(i) contained totally within the inner void of
the thin shell a volatile composition (which
may optionally be temporarily entrapped in
entrapment material and totally entrapped
in the entrapment material at least at the
instant in time of commencement of the functional
operation of the structure --- that is,
when it is removed from an air-tight package);
and
(ii) at least a finite section of said thin shell
compxising a porous polymer that is defined
by (i) the property of either transporting
water vapor at a rate of between about 50
up to about 1000 g/m2/day at about 25C
and at about 50~ relative humidity at about
atmospheric pressure and/or having an air
transport rate of 100-20,000 Gurley seconds
(Gs); and (ii) a thickness in the range of
from about 0.1 mils up to about 20 mils (e.g.,
a filled porous polymer containing embedded
therein a plurality of finite solid particles)
said porous polymer having a porosity such
that when said hollow totally enclosed structure
is located in an ambient envixonment said
volatile material molecules are either (a)
adsorbed onto the inner surface of the micro-
porous polymer section and desorbed from
the microporous polymer from the outer surface
of the shell at a substantially constant
mass flow rate both of the individual volatile
1353~
- 34-
compo~ents and totally flowin~ through
such porous polymer section, or (b) trans-
ported through the porous polymer shell section
by means of capillary action at a substantially
constant mass flow rate both of the individual
volatile components and totally flowing from
said thin shell the driving force of such
molecular transport resulting from a difference
in concentration of volatile substance between:
(x) the gas phase of the inner void of said
shell; and
(y) the space immediately adjacent the outer
surface of said microporous palymer shell
section.
The microporous polymer shell section (also referred
to herein as "lamina") useful in the practice of our invention
has the following specifications:
(i) The property of transporting water vapor
at a rate of between about 50 up to about
1000 g/m2/day at about 25C and at about
50% relative humidity at about atmospheric
pressure;
(ii) Porosity range: 100-20,000 Gurley seconds;
(iii) Most preferred porosity range: 8,000-12,000
Gurley seconds;
(iv) Range of Temperature for Operation: -80 C
up to 150C;
(v) Most preferred temperature ranye of Operation:
0C - 60C; and
(vi) A thickness in the range of from about 0.01 mils
up to about 20 mils.
~2(3~S3~
- 35 -
Certain statements concerning operation of the
microporous polymer film (~membrane~) of our invention are
based upon information disclosed in the paper: ~PERMEATION
OF PURE GASES UNDER PRESSURE THROUGH ASSYMETRIC POROUS MEMB~ANES,
MEMBRANE CHARACTERIZATION AND PREDICTION OF PERFORM~NCE",
Rangarajan, et al, Ind. Eng. Chem. Proc. Des~ Dev., 198~, 23,
78-87.
The term "polymer" in this case is intended to
include pol,vmers of varying molecular weights and degrees of
branching, homopolymers, copolvmers, terpolymers and the like,
including but no limited to substances such as polyolefins
(e.g., polypropylene), polyamides (e.g., nylon 66), poly-
fluorocarbons (e.g., TEFLON( )), polyesters, e.g. polyethylene
terephthalate, polycarbonates, (e.g., LEXAN(R)), polyacrylates,
(e.g., Lucite (R)) and blends of same in various molar ratios.
The term "membrane" is intended herein to define
porous polymeric shells, films or sheets, monolayer, bilayer
or multilayer which on functional operation of the structure
of our invention-and thereafter, will have the ability to have
transported therethrough volatile substances useful in the
practice of our invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 22B represents a graph of rate of fragrance loss (dqt)
versus time (resulting from a "burst effect") for the entire
period of possible continuous use of the structure of Figure 1
assuming that the structure of Figure 1 is not replaced at
discrete time intervals in an enclosed air-tight outer container.
Figure 22C represents graphs of fragrance loss versus time
in the case of a "burst effect" ~B) and in the case of a "lag
effect" (L).
~`
~z6:~S3~
36 -
Figure 23 represents a random section of a filled porous polymer
lamina (12,000 Gurley second film) magnification of 500x, using
a scanning electron microscope, which filled porous polymer
lamina is useful in the practice of our invention.
Figure 24 represents a random section of a filled porous polymer
lamina, (12,000 Gurley second film) magnification of 3500x,
using a scanning electron microscope, which filled porous
polymer lamina is useful in the practice of our invention.
Figure 25 is a plot of transport ra`tes (of water vapor)
versus temperature through filled porous polypropylene films
of the nature exemplified herein, infra.
Figure 26A is a series of graphs of time (elapsed hours~ vs.
grams water and fragrance lost from the article illustrated
in Figure 5 using various temperatures of operation. The data
points are set forth in Example V, infra.
Figure 26B is also a series of graphs of time (elapsed hours)
vs. gram water and fragrance lGst from the article illustrated
in Figure 5 using various temperatures of operation and working
specifically with a fragrance identified as "278m"~ The method
of obtaining such data is further specified in Example V, infra.
Figure 26C is a series of graphs of time (elapsed hours) vs.
grams water and fragrance lost from the article illustrated
in Figure 5 using various temperatures of operation and particularly
working with the fragrance ;n~ t~d at "394m" in Example V, infra.
Figure 27A sets forth graphs showing water transport through
filled microporous polymeric membranes useful in the practice
of our invention; and these graphs set forth mg. water lost
per day vs. temperature in degrees Kelvin.
Figure 27B sets forth a graph showing water transport through
filled microporous polymeric membranes useful in the practice
of our invention; and this graph sets forth grams water lost
per day per square meter vs. temperature in degrees Kelvin.
~'~
~z()U53V
Figure 28 is an Arrhenius Polot of the data set forth in Figure
~7A and sets forth the log (natural base) of transport rate
vs. reciprocal temperature (degrees Kelvin ).
Figure ~9 is a perspective view of a cell used for determining
the data as presented in the graphs of Figures 25, 26A, 26B,
26C, 2~A, 27B and 28.
Figure 30 is a side elevation view of the cell of Figure 29.
Figure 31 represents an "explosion" of the parts of the cell
of Figure 29 and is indicative of how these parts are put together
in order to enable the cell to be used to determine the data
presented in the graphs of Figures 2~, 26A, ~6B, 26C, 27A,
27B and 28, inclusive.
~igure 32 is a cut-away side elevation view of the cell of
Figure 29 looking in the direction of the arrows.
Figure 33 is a GLC profile of the frangrance material denoted
as "278m" employed in Example VI at time, t=0 weeks.
~igure 34 is a GLC profile for perfume composition "278m'^
employed in Example VI at t=2 weeks.
Figure 35 is the GLC proile for perfume composition "278m"
employed in Example VI at t=3 weeks.
Figure 36 is the GLC profile for perfume composition "278m"
employed in Example VI at t-4 weeks.
Figure 37 is the GLC profile for perfume composition "894m"
employed in Example VI at t=0 weeks.
Figure 38 is the GLC profile for perfume composition "894m"
employed in Example VI at t=2 weeks.
Figure 39 is the GLC profile for per~ume composition ~894m"
employed in E~ample VI at t=3 weeks.
Figure 40 is the GLC profile or perfume composition "894m"
employed in Example VI at t=4 weeks.
Figure 41 is a dual graph for perfume composition "278m";
the graph indicate b~ reference numeral "401" showing weight
lost over a period of time as measured in mg/cm2 and the line
,....
- -. ., "
~L20~?53(~
~ ",
- 38 -
indicated by reference numeral U402~ indicating odor intensity
vs. time (showing essentially no change in odor intensity)
where odor intensity is on a scale of 0-30 odor intensity units.
Fi~ure 42 represents a series of graphs indicating mg/cm2
evaporated of fragrance through the membranes; a filled poly-
propylene membrane (reference numeral ~411~) and non-filled
polypropylene membrane (reference numeral "412~) and in addition,
shows evaporation without the use of any membrane (reference
numeral "410") as specifically set forth in detail in Example
III, infra wherein the data points are set forth in tabular
form.
Figure 43 is another series of graphs showing evaporation in
mg/cm vs. time in days for fragrance which is a 2% mixture
of fragrance in Carbopol gel as specifically exemplified in
Example III. The graph indicated by reference "420" is a graph
for evaporation without any interference from a membrane.
The graph indicated by reference numeral "421" is the graph
showing rate of evaporation through a membrane which is filled
polypropylene and is a membrane defined according to our
invention. The graph indicate by reference numeral "422" is
the graph for evaporation through a polypropylene membrane,
not defined within the parameters of our invention.
The process of our invention comprises dispensing
continuously (as illustrated in Figure 20) or discontinuously
for discrete periods of time (as shown in Figure 2) at steady
state, a volatile composition of matter 3 from a container,
e.g. as represented by reference numeral 500" in Figure 1,
into the atmosphere surrounding said container ~nabled by the
use of a polymeric membrane that may be further defined by
having (i) the property of either transporting water vapor
at a rate of between about 50 up to about 1000 g/m2/day at
about 25C and at about 50% relative humidity at about atmospheric
pressure and/or having an air transport rate of 100-20,000
Gurley seconds (~s) and (ii) having a thic~ness in the range
of from about 0.01 mils up to about 20 mils~
~~ 'i;' '`
3L;2 (~53~
- 39 -
A typical example of porous polymer composîtion
of matter was described on page 15 of the Disclosure. Additional
examples are those where the air resistance (Gurley) varies
from about 8000 seconds up to about 12,000 seconds.
The microporous polymer membrane section useful
in the practice of our invention has the following speci~ications:
(i) Water vapor transmission rate: from about
50 g/m2/day up to about 1000 9/m2/day at
about 25 C and at about 50~ relative humidity
at about atmospheric pressure;
(ii) Porosity range: 100-20,000 Gurley seconds;
(iii) Most preferred porosity range: 8,000-12,000
Gurley seconds;
(iv) Range of Temperature for Operation: from
-80C up to + 150C;
(v) Most preferred temperat~lre range of operation:
0C up to 60C; and
(vi) A thickness in the range of from about
0.01 mils up to about 20 mils.
The statements concerning operation of the microporous
polymer membrane of our invention are based upon information
disclosed in the paper: PERMEATION OF PURE GASES UNDER PRESSURE
THROUGH ASSYMETRIC POROUS MEMBRANES, MEMBRANE CHARACT~RIZATION
AND PREDICTION OF PERFORMANCE", Rangarajan, et al Ind.Eng.
Chem.Proc.Des.Dev., 1984, 23, 79-37.
Rangarajan, et al hypothesizes that one of the
following five mechanisms are operative in working with the
microporous polymeric membrane as used herein, to wit:
~`,
3~2(3~53~
- 40 -
(i) Molecular diffusion (following Fick's Law);
(ii) Capillary:
(a) Knudsen Flow;
(b) Slip Flow; and
(c) Viscous Flow-
(iii) Adsorption/Desorption.
We show herein that the probability of mechanism
(i) contributing in any substantial manner to the operation
of our invention is negligible.
~lthough a filler is not required insofar as the
microporous polymeric membrane useful inour invention is concerned,
it is now preferred that a filler be incorporated therein having
an average particle size of from about 0.1 up to about 20 micro
meters.
Particulate or pulverulent fillers which are useful
in the practice of this invention include, but are not limited
to, clays, including both untreated clays and those which have
been surface-treated in various ways well known in the art,
ground limestone, talc, precipitated calcium carbonate, including
surface-treated t~pes, alumina, aluminium silicate, barytes,
wollastonite or other calcium silicàte, silica, zirconia,
titanium dioxide, and polymeric illers such as pulverized
phenolic resins, polyamides, (e.g. nylon 56), polyfluorcarbons,
(e.g. TEFLON(R)), polyesters, e.g., polyethylene terephthalate,
polycarbonates, (e.g. LEXAN( )) polyacrylates, (e.g. LUCITE( )).
The only limitations are that the fillers should
not adversely affect or react with the aromatizing or other
functional volatile substance or any entrapping material which
may be used in entrapping the aromatizing or other functional
volatile substance, or absorb the aromatizing or ot~er functional
volatile material to such a degree that release ~ro~ the microporous
. ! ~,
~2~)~PS~
~ ,
polymer membrane is unduly inhibited or entirely prevented.
Although the particle size of the filler can be varied over
a wide range, e.g., 0.1 micromemters up to 20 micromemters,
extremely coarse particles are generally undesirable because
they may detract from the physical functioning and mechanical
operability of the membrane which is the key functioning member
of the apparatus of our invention, as well the aesthetic qualities
of the finished microporous polymeric membrane.
The amount of filler can be varied over a wide
range depending on the amount of volatilizing material to be
released from the entrapped volatilizable substance 3 and the
vapor viscosity of the volatile vapor being transported (which
is either transported by means of capillary action and/or is
adsorbed onto and desorbed from the porous polymer). We have
found that filler levels in a range of from 5 to 100 parts
by weight per 100 parts of polymer are generally satisfactory,
although greater or lesser amounts can be used if desired.
Indeed, it is not necessary to use any filler so long as the
polymeric membrane has (i) the property of either transporting
-- 20 water vapor at a rate of from about 50 g/m2/day up to about
1000 g/m2/day at about 25C and at about 50% relative humidity
at about atmospheric pressure and/or having an air transport
rate of 100-20,000 Gurley seconds ~Gs) and (ii) a thickness
in the range of from about 0~01 mils up to about 20 mils.
., ~ .
;i3~
- 42 -
In each of the graphs wherein perfumed material
is used, it is apparent that for the major portion of
the useful life of the structure, e.g. structure 500,
the rate of mass transport of perfume substance, when
in use, is n o n order, that is:
dq = k
wherein k is a constant and q is measure of the output
of volatile substance for the outer surface of the outer
polymeric membrane of the article of our invention.
Discussion covering the preparation of the compositions
of matter which constitute the fragranced gels and
unfragranced gels whereby the graphs as represented by
reference numerals 201, 202, 203, 204 and 205 of Figure
18 are prepared is set forth in Examples I and II, infra.
By the same token, in Figure l9, the graph indicated
by reference numeral "302" indicates percent fragrance
loss versus time for a fragrancing gel containing 2%
by weight fragrance but not enclosed in a structure defined
according to our invention. It will be noted that the
diffusion of perfume compositions or other volatile
substances as stated he~in~eeo~eis in accordance with
the ordinary diffusion law and is not steady state,
to wit:
dq ~ Constant
Discussion covering the preparation o the
compositions of matter which constitute the fragrances
and fragranced gels whereby the graphs as represented
by reference numbers "4107', "411" and "412" in Figure
42 and reference numerals "420", ~'421" and "422" in Figure
43 are prepared as set forth in ~xample III, infra.
The graph indicated by reference numeral "410"
in Figure 42 indicates mg/cm2 evaporated of fragrance
s~
- 43 -
where the fragrance is not enclosed in a structure defined
according to our invention. The graph indicated by reference
numberal "411" in Figure 42 is for the same fragrance
(indicated as "EGL-1433")(as more particularly described
in Example III) located in the thin shell structure of
our inventi~n as illustrated in Figures 1, 2, 3 and 5.
The graph indicated by reference numeral ~412" indicates
percent fragrance loss (mg/cm2) vs. time for the same
fragrance (EGL-1433) located in a thin shell structure
wherein the membrane rather than being a membrane as
defined for use with our invention ((i) having the property
of either transporting vapor at a rate of between about
50 g/m2/day up to about 1000 g/m2/day at about 25C and
at about 50~ relative humidity at about at atmospheric
pressure and/or having an air transport rate of 100-20,000
Gurley seconds (Gs) and (ii) a thickness in the range
of from about 0.01 mils up to about 20 mils) uses a poly-
propylene membrane which has properties including a
water transport property outside of the range of the
properties of the membranes useful in our invention.
In Figure 43, the graph indicated by reference
numeral "420" indicates fragrance loss (in mg/cm2
evaporated) vs. time for an air freshener gel containing
2~ by weight fragrance but not enclosed in a structure
defined according to our invention.
The graph indicated by reference numeral "421"
is for the same fragrance gel containing 2% by weight
fragrance (as more particularly described in Example III)
located in the thin shell structure of our invention as
illustrated in Figures 1, 2 and 3.
~0~530
- 44 -
The graph indicated by reference numeral ~422"
in Figure 43 is for the same fragrance gel containing
2~ by weight fragrance (as more particularly described
in Example III) located in a thin shell structure of our
invention as indicated in Figures 1, 2 and 3 wherein the
membrane of the structure of our invention is replaced
by a polypropylene membrane having an infinite resistance
(as being essentially non-porous).
Figure 22B is a graph of ddq versus time (resulting
from a "time burst" effect after a buildup of fragrance
within the totally enclosed structure of our invention)
wherein the period of from to to tl is a condition of
"unsteady state" mass transport (usually no more than
a few minutes) and the period from tl to t2 is a condition
of "steady state" mass transport; a very long period of
time, e.g., 55-75 days and even longer.
Figure 22C shows graphs of fragrance loss versus
time in the case of a "burst effect" (graph "B") and in
the case of a "lag effect" (graph "L"). Reference: Robinson
"Sustained And Controlled Release Drug Delivery Systems"
published by Marcel Dekker Inc. (1978), pages 258 and
259.
V5;~0
!!
" - 45 -
Figures 23 and 24 set forth scanning electron microscope
photographs of porous polymer film filled with CaCO3 filler.
~igure 23 is a photograph showing 500x magnification. Figure 24
is a photograph showing 3500x magnification.
In Figure 25, (which is a plot of transport rate of water
vapor versus temperature in degrees centigrade), the graph
indicated by reference numeral "250" is a graph of transport
rate ~ersus temperature for film having a porosi~y of, nominally,
8000 Gurley seconds.
The graph indicated by reference numeral "251" is a graph
o~ transport rate versus temperature for water loss from a
silanized 8000 Gurley second film (the silanization being
carried out by treatment with a trimethylchlorosilane
silanizing agent).
~he graph indicated by reference numeral "253" in ~igure 25
is a graph of transport rate versus temperature in degrees
centigrade for rate of water loss from a nominally 12,000
Gurley second filled polypropylene film.
The graph indicated by reference numeral "252" in Figure 25
sho~s transport rate versus temperature in degrees centigrade
for rate of water loss from a silanized nominally 12,000 Gurley
second film.
;' The graph indicated by reference numeral "254" is a graph
' of transport rate versus temperature in degrees centi~rade
, for rate of water loss from an untreated non-porous non-filled
polypropylene film.
.....
,~i~'.
~ ~L
s~
- 46 -
.,
Both treated and untreated films as depicted in the graphs
in Figure 25 were placed into diffusion cells as illustrated in
~igures 29-3~, inclusive which were loaded with distilled water.
The cells were then placed in a constant temperature/humidity
, oven at 25C and 63.5% relative humidity. These conditions
. I provided for a nominal water vapor differential of 10 Torr
between ~he inside and the outside of the cells. After ~wo
days, the temperature was adjusted to 35C and the relative
humidity to 79~ providing $he same nominal 10 Torr water ~apor
pressure differential.
The graph indicated by reference numeral "253'l in Figure 25
is a graph of transport rate ~ersus temperature in degrees
centigrade for rate of water loss from a nominally 12,000 Gurley
second filled polypropylene film.
The graph indicated by reference numeral ~254" is a ~ra-h
of transport rate versus temperature in degrees ~enti~rade for
rate of ~ater 105s from a non-porous, non-filled polypro~i~er.e
film.
The films as depicted in the ~raphs in Figure 25 ~:ere r,la-ed
into diffusion cells as illustrated in Figures 28-31 which ~ere
loaded ;ith dis~illed water. The cells ~ere then placed in a
ccnctant temperature/humidity oven at 25C and 63.5~ relati-e
hur.,idity. These conditions provided for a no~inal ~a!er ~-aror
di'ferential of 10 Torr between the inside and the outside o'
the cells. After t~o da~s, the temperature has adjusted to
3;C and the relative hur..idity to 79~ providing the sar.e
no-.inal 10 Torr ~ater vapor pressure differential.
3 5 3 ~
- 47 -
Figure 29 is a perspective view oE the diffusion
cell which was used in order to obtain the data set forth
in Examples III, IV, V and VI, infra. Figure 31 is an
exploded view of the cell of Figure 29. Membrane 290
is placed in gland 291 and gland 291 is placed into sealed
cap 293 causing the membrane 290 and the gland 291 to
be firmly in place and threaded into the sealed cap 293
using lock nut 292. The sealed cap 293 previously has
the liquid or gel substance the properties of which are
being measured, located ~ithin it for the purpose of testing
the porosity of membrane 290.
During the testing, volatile substance passes
through me~brane 290 into the surrounding atmosphere at
294 as shownin Figures 30 and 32. Sealed cap 293 is shown
to be screwed in place using lock nut 292 holding membrane
290 on gland 291 in Figures 30 and 32.
The details concerning Figures 26A, 26B, 26C,
27A, 27B 28 and 41 are set forth in Examples V and VI,
infra.
Thus, the physical rationale or "mechanism" for
operation of our invention may be (i) "a steady state"
adsorption/desorption mechanism or ~ii) by means of capillary
action; or (iii) a combination of adsorption/desorption
and capillary action. The adsorption/desorption mechanism
would be operable, for example, as a result of the critical
surface tension of the filler phase being greater than
the critical surface tension of the volatile composition
existing in the liquid state in the device o~ our inventionO
. . ,~,,
~i '
`, ~Z0~53~)
- 48 -
.,
EX~MPLE III~A)
Into a group ~ three jars incicated as (i), ~ii) o'.C
each ha~ing an opening havin~ an area of of 15.48 c~2, a ~.~ir~.
o~ 4.2 cm, an ~pening diameter of 4.4 cm and an internal
dia,meter of 4.8 cm (total volume: 72.5 cc) is placed 5~00 r~
; (5 grams) of the f~llowing ~erfume CQmDosition.
Inoredients Parts ~v h'eioht
Citrus oil distilled .......................... 275
Dipentene...................................... 150
~he ~,ixture of compounds
avin~ the structures:
1~`~'
uod
R~S - - - - - - - - .. 130
~re?ared aecording to
r~ . S . Letters Patent
4,330,416 issued on
';ay 18, l9S2 tthe
s~ecification for which
is incorporated by
reference herein)
Geraniol........................................ 50
Tetrahydro ;luguol.............................. 50
~emon oil....................................... 5Q
Grapefruit oil.................................. 50
Geranonitrile................................... 25
n-Octanal...........~........................... 20
n-Nonanal.................................. ..... 20
n-Decanal.................................. ..... 10
Citronellol....................O................ lO
~-(4-Per.tenoyl)-3,3-dimethv~
cyclohexane 1............................ .... 25
Beta pinene................................. ..... 5
n-Nonanol................................... .... 20
Cis-3-hexenyl formate..~.................................. , 5
Cis-3-hexenol.......... O... ~............................... 10
~ethyl jasmonate.. O.....O................................. 2S
Dihydro methyl jasmonate..........O........................ 20
12~3~DS30
~ 49
Jar ~i) i5 left open and the eva~OratiGn of th~- a!,-~.c-
fra~rance for~ulation is measured on a dail~ ba~is.
; Jar (ii) is co~ered in a tight fitting manner wit~. a
, me.~.~rane ha~in~ the followins specifications:
S ' Composition ~o~ypropylene ~ CaC03 filler
Thickness 100 micrometers
~'eis~t 90 q/m
Ultimate tensile ~trength 30 M~`/r2 (ma~hine dire_tio)
11 M`;/m2 (~ran~v~rse dire~ti~
Elongation at break iBo~ (machine direction)
~50~ (transverse direction)
~ore size O02 micrometers (ræx)
Void volu~ 0.34 cm /g (30~)
De~sity 900 kg/m
Air flow 3 cm3 /cm /rin at 1 k-/cm
~ater flow O.OGl cm3/c~2/r~in at ; kS/c-2
Air resista~ce (Gurley) a ,ooo seconds
h'ater vapor transmission 1~0 5~F.. ~24 hrs at 23C a. 5J~
re ative humidity
Ther~.al sta~ility lD hrs at 13DCC
Jar (iii) is covered in a ~i~ht fittinc ~anner with a
pol~rrop~lene film of 1 mîl thickness. In each of the jars
the rate of e~aporation of the fragrance is measured on a
daily basis. The weight .oss occurs at constant ter.~erature,
22C and constant relative humidity, SO~ relative hu-.idit~-.
Ta~le I set forth below shows weight loss as a function of
ti~e and w~ight loss per square cen~i~e~er as ~ function of time
for each of jars (i), lii) ~nd (iii).
,
. . .
;: -
TA BI,E
JAR (i~ Jt\n ~ JM (iii~
n~ of pc~rf~ne ~,~g/cm2 of ~rflme mg o~ ~rf~ mg/an of ~r~ mg of ~rh~r~ ~/sn2 of r~erf~
Daysc~ ion lost c~ ition lori~ ~nTy~.s~tion lo~t c~ition kr.t ~or~ition lc~st c~ositinn lr7~t
130 12 . 3 80 5 20 1 . 3
2 4~0 - 150 . - 5~ -
3 G30 45.0 23~ 15 8~ 5.
6 1070 69. 0 31~ 24 120 8.
7 1330 - 43t~ - 140
9 185~ 119.0 56r) 36 20~J 13.Q
~0 15 2310 1~9.0 ~8~ 57 31~ 20.
31 2660 172.0 145~ 94 600 39.0
36 2740 177.0 156~ 1~0 680 44.0
o
The series of graphs set forth in ~i~ure 42 lndicates ~raphically the results set forth in Table I,~u~ra.
Thus~ the graph indicated by reference numeral "410" is the qra~h for the rate of fraqrance comnosition
evaporation from Jar (i). ~he graph indicated by reference num~ral "411" is the ~ranh for the rate
o evaporation of fragrance eompvsition from Jar ~ii). The ~raph ~ndicated by reference numeral "412"
on Fiqure 42 is ~he graph for the rate oF evaporation o~ fraqrance com~osition from Jar (iii).
.. . . . . . . . . . ... . . ..
` ! lZOt~530
'i
- 51 -
EX~iPLE III(B)
i'
Three jars are provided, Jar (iv), Jar (v) and Jar (vi)
having dimensions identical to those of Example III(A). To
i;each of the jars, 20 grams of a perfumed gel is added which
1 is prepared as follows:
1, ~
i~ n3 .o Parts by weight of Carbopol ~ 940 (manufac~ured by
the B. F. Goodrich Company) (see Note 1 of Example I) is
sifted into the vortex of rapidly stirring water
(88.8 parts by weight~ containing 0.2 parts by weight
of methyl paraben at a temperature of 220C. The
mixing is continued until a smooth cloudy dispersion is
formed. 2.0 Parts by weight of the perfume composition
of Example III(A) is added to the prepared ~lurry and
the slurry is continued to be mixed until the perfume
composition is dispersed. The slurry is neutralized
with 6.0 parts of weight o diethylpropenol~amine (50%
solution in water) using 510w mixing to avoid the in-
clusion of air."
Jar (iv) is permitted to rer.ain open ~hile measure-er. s
for ~eisht loss of gel are made on a daily basis.
Jar (v) is tightly co~ered with a me~brane hauing the
sa...e specifications as the me.~rane used to co-er Jar lii)
in Example III(A) and the weight loss is measured on a dail~
basis.
Jar (vi) is covered with a polypropylene film hat~in~ a
t~,ickness of 1 mil and the weight loss of the gel is meas~red
on a daily basis.
~. .
,i ~20~53~
.
- 52 -
~ able Il, below sets forth weight 1oss as m~a~ured in
m~,~c~2 for each of Jars (iv), (v) and (vi):
T,.BL~ I I
;
Da~-s J~R (iv)JAR (v) J~R (vi)
~ ,7 2
(mg/cm )(m~/cm~) ~ms/cm )
1 13~ 28 0.7
3 555 113 2.0
6 lOD7 219 ` 2.0
~ 1201 349 3.g
15 12~7 57~ ~.5
31 1210 lQ83 9.0
36 1209 1154 9.7
Figure 43 is a ~ranhical representation of the results
se~ forth in Ta7~1e II, supra. The ~ra~h indicated b~ refererce
n~-eral "420" is the gra?h for the open jar, Jar (i~7) (.-,'c '
VS7. time). The graph indicated by reference numeral "~21" is
the sraph for the weight loss of gel from Jar (~ he c~
incicated b,~ reference nu~eral "422" is the ~ra-h for t..e
we~ght loss of gel fro~ Jar (~i) a5 a function of tir,e.
!
~2~ 530
ji - 53 - !
.,
il
EXA'lPLE IV (A)
The following experimental design was established through
j an evolutionary process in order to determine the permeability
,j of water vapor through filled polypropylene film as exemplified
5 ¦ I on Page 21l supra.
I
Cell Design
Stainless steel 316 diffusion cells as illustrated in
~isuxes 28-31, inclusive the details for which are set forth,
s~pra, were specially designed to measure the transPort of
s~all a~ount of ~ater vapor throu~h a film sample under
controlled experimental conditions. Commercially a~aila~le
~ittinss ~nut, plug and glands) were modified to acco~mo~ate
~ater or a volatile substance in one side of the gland and
a film specimen between the two glands. '
IIo Materials
A. Films: A film designated as having a nominal air transport
rate of 12,000 Gurley seconds (Gs) was e~?lo~ed. Six sa-ples,
each measuring 6" x 6", were cut from the center of a 10" ~ide
stock sample. From each ~f these test samples, a sam?le
ap?rQximately 2.0 cm in diameter was used for the permea~io~ ',
experi~ents and a s~ple of a?proximately 5" diameter was used
for air per~eation measurements. Approxi~ately 0.5 g of ~ater
were used in each o~ ~he test ~ells.
1 B. Silylation procedure: Trimethylsilyl chloride (20 gms)
25 ~ was placed in a 200 ml beaker and placed in a glass desicator.
Three of the 6" x 6" test samples were suspended inside of the
desicator and the desicatDr was closed tightly and placed in a
45C oven overnight. The beaker was then removed from the
desicator after it returned to ambient emperature. The desicator
was then evacuated at approximately 20 mm/Hg for a p~riod of 4~5
hours to remove residual volatilesO The films were then used
for the experimen~al procedure.
C. Water: Approximately O.S g of water were used in each
of the test cells.
; !
Il ~2~53~ 1
- 54 -
!'
III. Environmental Conditions
A. Oven: A Blue "~" controlled tem~erature and hu~idity
ove~ was used for all experimental conditions. Theter~erature and
hu~.idity conditions were controlled by t~e dry and wet bulb
thermome~ers located inside of the test chamber.
B. Conditions. The following conditions were use2 in the
experiments:
Temperature ~C) 25 30 35 40 45 50 55
Relative Humidity (%) 50 63 72 78.5 83.5 89 90
These conditions established a relative water vapor press~re
difference of 15.85 mb between the inside and outside ~f the cell.
C. Ter..perature conditions: The following se~.uenc~s of
te.,?eratures (C) were employed to randomize the sam~le treG~D...
a-.~ re~uce ~ossible systematic error:
(A~ 25 - 45 - 30 - 40 - 55 - 35 - 25 - 35 C
(B~ 35 - 50 - 30 - 45 - 25 - 35 - 40 - 25 - 30C
IV. Sam~le heiching
The cells were placed in the oven at the selected te-per2ture
condition so that the film was in the "up" position as irdica.
in Fig~res 30 and 31. After the sar,ples were e~uilibrated for
at least 10-12 hours, ~he sarples were weighed using a ~le~tler
-163 electronic balance interfaced to the Disital E~uip~er.t
Corporation (ISalnard, r~assachusetts) VAX ~ 11/7B0 computer. The
samples were then replaced in the oven and were reweighed
after approximately 12 hours to ~iv~ the transport rate for
each condition. ~ive re?licates were run and ~arm~les ~ere
re-tested at 25, 30 and 35C ~o monitor reproducibili~.
,~
il ~2q)~s3~
jl - 55 -
V. Da~a ~andlinq
A11 data were entered directly into the Va~: 11/7B0 c~~.,.,ut~r
u~ing s~ecified sof~are in ordcr to faci1itate t},~- c~lc~-
;~ion of weight-loss, the plotting of graphs, and the ~.2,.ipU-
lation ~or com?utational purposes~
; VI. Experimental Details
~ xperiment using ~000 ~s and 12,000 Gs films, regular
and silylated, ~t 25C ~50~ R.H.), 35~C (71~ R.H.) and
4;C (83~ R.~.).
In Pigure 25 (which is a plot of transport rate of water
vapor versus temperature and degrees centigrade) the graph
indicated by reference numeral '`250" is a graph of transport
rate versus temperature for 8,000 Gurley second film which is
not treated (silylated).
lS The graph indicated by reference numeral "251" is a graph
of transport rate versus temperature for water loss from a
silanized 8,000 Gurley second film for the three temperatures,
25C, 35C and 45C.
The graph indicated by reference numeral "253" in ~igure 25
is a graph of transport rate versus temperature in degrees
centigrade for rate of water loss from a nominally 12,000
Gurley second filled polypropylene film at temperatures of
25C, 35C and 45DC.
The graph indicated by reference numeral ~252" in ~igure 25
shows transport rate versus temperature in degrees centigrade
for rate of water loss from a silani~ed nominally 12,000
Gurley second film at 25C, 35C and 45C~
The results of this study are:
(i) Diffusion of water through a filled polypropylene
matrix (membrane defined according to the properties
set forth on page 21, supra) does not contribute
significantly to the mechanism of the total ~ransport
through said film;
S3~ 1,
- 56 -
(ii) A "high" activation energy process (such as viscous
capillary flow~ appears to contribute significantly
to the transport of water through the filled poly-
propylene films especially above 40~C; and
(iii) A "low" activation energy process (such as sorption-
i driven surface flow) appears to contribute signifi-
cantly to the transport of water through the filled
i polypropylene films especially below 40C.
.
53~3
"
' - 57 -
EXP~IPLE IV(B)
. .
~he following Table III ~h~h~s ~he air resistance ratin~
of 15 films measured in Gurley seconds and the minimu~ an~
; maximum water ~ransport rates that were ~bserved at 25~C a-.
'~ a~ 50~ relative humidity. The measure~ents were carried o~t
using cells and pr~cedures substantially as described in
ExamFle IV(A~, supra.
TA9LE III
h~.~R T.~:C.~ A~ 25C
~nimum Water ~;~ ~ Wate~
Fi1~ o. tir Resistance Transpoxt Rate Transport Rate
~C~ ley seconds) (g~m2/day)(g~m2/day)
1 1600 370 ~83
2 2100 50B 667
3 3100 434 603
3200 249 593
3300 439 651
6 4003 375 4~1
7 4300 339 751
8 4300 413 677
9 540~ 143 ~1
600~ 140 34~
11 670D 243 333
12 7000 249 60B
13 7100 222 280
14 1020~ 222 317
10B00 169 193
1~3~S3(3
- 58 -
EX~MPLE V
"
J~.._~lALS
'I~ A. TE~T PR~D~CT5: Eigh~ samples o~ the articl~s as
'1, illustrated in Figure 5.
5 , B. ~ECT C~ ERS: The ~est char.~ers were construc~ed
~rom white polypropylene canisters of 5 gallon li~ id
volume which has been fitted with an air-tic~t lid.
The lid had a 2 inch evaluation hole cut in t~e ~
~.hich ~s fitted with a cork stopper. ~nci~idual sc~ s
were placed in the cha~ers approxir.iately 1 hour ~rior
,. to e~aluation to permi equilibration.
C. J~'DGES: A panel of 23 individuals trair,ed and ckille~
in the practice of ma~nitude esti~.,ation ~ere e.~-,lv~e_
as odor intensity judaes. The jud~es ~ro~ide~ r2~ io-
scaled assess~ents of the percei~ed odcr in~ensit.~.
D. CO~ROL S~:r'LES: The follo~ina control sa~ les were
ir,corporated into the ex~erimertal design:
1. 100 g Unfragranced ~el, fully exposed fro.. a petri
plate, the gel being prepared in accordance ~ith
the process of Exa~rle III(B).
2. 100 g ~racranced Gel ("894~."), full~ ex,oce~
from a petri plate (prepared accor~inq to t~e
procedure of Exa~.~?le III~B).
E. S~`~PLE E~PO~ E: Du~licate sa~les ~ere schedl_le~ ~or
ar.~ient roo~ ex~osure based upon a cor.ver~in~ cr-le~ic~
design so that sa...rles re~resenLing 0, 2, 3, an~ 4 ~e;~
of exposure ~ere a~ailable at the date of t~,e ser.~or.
~est~
~T~O~S
~11 exposed samples were submitted in the blind ~o the par.el
, of jud~es after 1 hour in the test ~ha~bers. ~ total of 22 s~les
~ere evaluated in the test. All ~es~ ~a.?les were ra~ ed
upon sub~ission ~o ~he judges and re-rando~,ized peri~ically
t~,roughout the evaluation period.
The magnitude estimation sensory data ~reference: Warren,
C.B., Paper No. 3 "De~elopment Of Fragrances With Functional
Properties By Quanti~at,i~e Measurement Of Sensory And Physical
Parametexs"; Moskowi~z and Warren "Odor ~uality And Chemical
Structure", American Chem.icals Society Symposium Series
, 148 (American Chemical Society - Washington, D. C., 1981) was
normalized by the method of 'no standards". Standard errors
- ; of the measurements were calculated to detenmine he significance
of the perceived test sample intensities.
" ~ 5~
- 59 -
A`;.~L~ICAL DA~A
The cu~lative weisht-l~ss ~-as ~taine~ during the e~c~re
peri~d f~r each ~f the test samples (excluding the cor,trc~s
a~ the 2ero-time sa~ples). The peri~dic weio'r,inas w~re c~
~n~ rep~rted as Cumulative Weight-l~ss vs. time and this i5
s~o~n in ~igures 26A, 26B and 26C.
; R~S~LTS
The su~r,arized sensory testing results are prese..te~ f~r
fra~rance "894m" in Table IV, infra. The nor~alized prc~u^t
~eig~t-loss data for "8g4m" are incorporated int~
~he last t~o columns of this Table ~IV) and repGrted
gra?hically in Figures 26A, 2SB and 26C.
~ he graph indicated by reference numeral "260" is the
grarh sho~ing grams loss ~f gel vs. time for four wee~s of
ex~sure of gel containing frasrance "2?Br.".
~ he graph in~icated by reference numeral "2~2" is the
graph sh~wins the mean weight loss after 4 ~eeks of ex.posure
for the gel containing fragrance "~94m".
The graph indicated by reference numeral "264" is the
craDh showins ~he ~ean weight l~ss rate for gel co~air.lnc
frasrance "2~8~" after 3 ~eeks.
~ he sraph indicated by reference nu~,eral "263" is ~-.e
gra~ shohing the mean weight loss of a gel containing
fragra~ce "894m" a~ter 3 weeks.
~he graph indicated by reference numeral "265" is the
srap~ shc,~ing the mean weight l~ss of a fra~ra~ced gel cc-.~air
fra~rance "278~" after 2 weeks exposure.
The graph indicated by reference numeral "261" is t~e
graph of the mean weight lcss of a gel containing frasrance "894."
after 2 weeks exposure~
Graphs 260, ~64 and 265 are sh~wn separately on Fi~ure 2~.
Gr~phs 261, 262 and 263 of ~igure ~6A are sh~n s~2rate!~
in ~igure 26C.
53~3
- 60 -
DISC~SSION
The results of the sens~ry experiments suggest that there
is a critical equilibration point sometime between "zero" and
2 weeks. This is reflected in the intensity decay between these
~wo evaluation points in this experiment.
The product containing fragrance "894m" did not ~how any
significant perceived odor intensity decay over the period
of 2 thru 4 weeks of exposure.
SU~ ~RY
10 , The results of this study indicate that the product
fragranced with "894m" quickly equili~rates to what is
perceived as a "steady-state" fragrance delivery rate over
a 4 week period.
3(~
- 61 -
EX~1~E Vl
AIR FRESY.r~;lR P~ODUCTS
~ERI~LS
Air fresheners ~roduced accordin~ to Example V an~ used in
said Ex2.,~1e V were then utilized for this example.
GLC anal~sis ~as performed on dual 50 meter fused silica
ca?illar~ colu~,ns containing OV-l or Carbohax 20~ licuid p.~aae_.
.~_,:~ODS
Aliquots of the test sarples were prepared for a~al~sis by
Flacing 5 sra~s of sa~?le, in a shaker jar with 25 ~ls Or
food grade ethanol and shaking on a wrist-action sha~er fcr
a?proximately 24 hours until no additional rolor could be re.
frc~ the gelatinous residue. The ethanol solution was
quantitatively decanted and the gelatinous resi~ue was washe~
with an additional l0 ~1 of food grade ethanol. The extr~-t
and wash were co~bined, d ~ ted volumetrically to 50 ml a~d
fil,ered usi~g a Milipore filter.
RE C7~ S
GLC analvsis of the isolates confirme~ that the pr~file o~
the isolate was consistent hith that of the original fra~ra.~ce
oil.
The results of the internal standard GLC anal~-ses are pre-
sented (a) for fragrance 278m on Carbo~ax 20~ in Figures 33
~0 weeks), 34 (2 weeks), 35 t3 wee};s) and 36 (4 weeks~ ar.d
(b) for 894m on Carbo~ax, 20,1 in Fi~ure 37 (0 weeks), 38
(2 weeks), 39 ~3 weeks) and 40 (4 weeks).
Fisure 4l sets forth a dual graph of weigh~ loss ~s. time
for 27~m las shohn by the graph indicated by reference numeral
"401")and for odor intensity on a scale of 0 to 30 units as
shown hy ~he graph indicated by reference numeral "402".
;
DISCUSSION
~he iso'ates were subjected ~o internal standard capillary
GLC to confirm sensory evaluations. In comparing the GLC
results across the 4 week period, it is obvious that there is
no apparent disproportionation of the fragrance over the
4 week exposure.
~.,
i
~2~?53~
- 62 -
TABLE IV
. QUA~iTITA~IVE OF ODOR "EVALUATION OF '.
! PRAGRANCE" "894m" BY MAGNITUDE ESTI~ATION
, Fragrance: "894m"
No. of Panelists: 23
'.
,~ mg~.
Exposure ~an b Std. Average Std. a Fra~. Loss
, 5ample Indent. Time Intensity Errora Intensity Error Nom, /Ave~ ;
Con4ro1
~ray~lced Gel 0 hrs. ~0.3 1.05
77.5 1.05 78.89 ~.04
Ze-o ~ime16 hrs. 53.1 1.13
52.6 1.10 52.87 1.0~
2 l~e~s 319 43.0 1.07 ~6.4
4~.9 1.10 43.94 1.06 6~.7 ~7.6
3 ~}s ~82 51.1 1.05 54.2
41.1 1.12 45.83 1.06 55.~ 55.0
4 We~s fi46 36.1 1.09 59.5
` S7.0 1.05 45.36 1.05 65.~ 62.6
~ Ge~etric means are calculated for all intensities. 5t~dard erro~s
sho~ld be read as 1. ~ ~ error, e.g., 1.13=13~ relative errcr.
A l-cdel~e odor Lntensity has a Yalue of 30 on ~his scale.
I' i
., O
11 1
'.
..~
