U.S. patent number RE32,513 [Application Number 06/842,486] was granted by the patent office on 1987-10-06 for method for dispensing at a visibly detectable rate, continuously or discontinuously, for discrete periods of time at a steady rate, a volatile composition of matter from a container into the atmosphere as well as the container used in the method.
This patent grant is currently assigned to International Flavors & Fragrances Inc.. Invention is credited to Marina A. Munteanu, Geoffrey B. Seaber, Augustinus G. van Loveren.
United States Patent |
RE32,513 |
Seaber , et al. |
October 6, 1987 |
Method for dispensing at a visibly detectable rate, continuously or
discontinuously, for discrete periods of time at a steady rate, a
volatile composition of matter from a container into the atmosphere
as well as the container used in the method
Abstract
Described is a hollow container comprising a shell which is at
least partially porous, containing an entrapped volatile substance
and a process for dispensing the volatile substance at a visibly
detectable rate, continuously or discontinuously, for discrete
periods of time at a steady state, the volatile composition being
in the alternative, a perfume composition, a deodorant composition,
an air freshener composition, an insecticide composition, a
herbicide composition, an odor masking composition, a pheremone
composition, an animal repellent composition, or an insect
repellent composition. The said container containing the entrapped
volatile substance ceases to operate, discretely, when said
container is placed in an outer air-tight container. The structure
consisting of the outer container and the inner container is also a
part of our invention.
Inventors: |
Seaber; Geoffrey B.
(Ijsselstein, NL), van Loveren; Augustinus G.
(Ryebrook, NY), Munteanu; Marina A. (New York, NY) |
Assignee: |
International Flavors &
Fragrances Inc. (New York, NY)
|
Family
ID: |
26937309 |
Appl.
No.: |
06/842,486 |
Filed: |
March 21, 1986 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
620239 |
Jun 13, 1984 |
|
|
|
Reissue of: |
245542 |
Mar 19, 1981 |
04387849 |
Jun 14, 1983 |
|
|
Current U.S.
Class: |
239/6; 239/34;
239/54; 239/56; 239/60 |
Current CPC
Class: |
A01N
25/18 (20130101); A61L 9/12 (20130101); A61L
9/042 (20130101); A61L 9/01 (20130101) |
Current International
Class: |
A01N
25/18 (20060101); A61L 9/12 (20060101); A61L
9/04 (20060101); A61L 9/01 (20060101); A61L
009/04 (); A61L 009/01 (); A61L 009/12 () |
Field of
Search: |
;239/6,34,53,55,56,60,54 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
52650 |
|
Aug 1977 |
|
IL |
|
55-78965 |
|
Jun 1980 |
|
JP |
|
55-81655 |
|
Jun 1980 |
|
JP |
|
55-36515 |
|
Sep 1980 |
|
JP |
|
8020178 |
|
May 1980 |
|
NL |
|
WO81/00051 |
|
Jan 1981 |
|
WO |
|
Primary Examiner: Nase; Jeffrey V.
Attorney, Agent or Firm: Liberman; Arthur L.
Parent Case Text
.Iadd.This is a continuation, of application Ser. No. 620,239,
filed 6/13/84, now abandoned, which, in turn, is a reissue
application of U.S. Letters Patent, Ser. No. 245,542 filed on
3/19/81, now U.S. Pat. No. 4,387,849 issued June 14, 1983.
.Iaddend.
Claims
What is claimed is: .[.1. A hollow totally enclosed structure
comprising a thin shell totally enclosing an inner void, said thin
shell having a base portion and an upper portion, said base portion
having an inner surface:
(i) at least a finite portion of said thin shell being transparent
whereby that portion of said inner void which is located proximate
to the base portion of said totally enclosed structure is visible
from without said thin shell, in the presence of visible
wavelengths of light;
(ii) contained totally within the said inner void of said thin
shell and in place on said inner surface of said base portion, a
volatile composition temporarily entrapped and totally entrapped at
least at the instant in time of commencement of functional
operation of said structure, in an entrapment material, said
volatile composition being selected from the group consisting of
perfume compositions, herbicide compositions, insecticide
compositions, animal repellant compositions, air freshener
compositions, pheremone compositions, odor maskant compositions,
deodorant compositions and insect repellent compositions;
(iii) at least a finite section of said thin shell comprising a
microporous polymer and termed "a microporous polymer shell
section" having a porosity such that when said hollow totally
enclosed structure is located in an inert gas at a pressure of less
than or equal to about 1 atmosphere, said volatile material
molecule are transported at a constant linear velocity and at a
constant total derivative of concentration of volatile substance
with respect to time onto the inner surface of said microporous
polymer section via an adsorption mechanism and from the outer
surface of said microporous polymer section to the surrounding
atmosphere via a desorption mechanism..]. .[.2. The hollow totally
enclosed structure of claim 1 wherein said base portion is
non-porous and transparent and said upper portion is a microporous
polymeric membrane and is opaque at least at the instant in time of
commencement of the functional operation of said structure, said
base portion being sealed to said upper portion..]. .[.3. The
hollow totally enclosed structure of claim 2 wherein said upper
portion consists of a microporous polymeric membrane which 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..]. .[.4. The hollow totally enclosed structure of claim 1
wherein the microporous polymer is 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 least one organic polyisocyanate, water and at least
one catalyst..]. .[.5. The hollow totally enclosed structure of
claim 1 wherein said microporous polymer is a 3-dimensional
microporous cellular polymer structure comprising a plurality of
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 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 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) having a value in the range 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 thermoplastic polymer which is a polymer
or copolymer of an ethylenically unsaturated monomer, a
condensation polymer, a polyphenylene oxide or a blend thereof..].
.[.6. The hollow totally enclosed structure of claim 1 which is in
the shape of a cylinder, the ends of the cylinder being translucent
and non-porous and the side of said cylinder being opaque at least
at the instant in time of commencement of the functional operation
of said structure, said side consisting of a microporous polymeric
structure..]. .[.7. The hollow totally enclosed structure of claim
3 wherein the thickness of the microporous polymer is about 100
millimicrons; the pore size is approximately 0.2 millimicrons; the
void volume of the microporous polymer is approximately 34 cubic
centimeters per gram and the density is approximately 900 kilograms
per cubic meter..]. .[.8. A structure comprising (a) a first hollow
totally enclosed structure defined according to claim 1 and
enclosing said first structure, (b) a second air-tight totally
enclosed structure, said first totally enclosed structure having a
volume less than said second air-tight totally enclosed structure,
said first totally enclosed structure being of such dimensions that
it is (i) enclosable within said second air-tight totally enclosed
hollow structure, and (ii) the internal volume of said second
air-tight totally enclosed hollow structure is greater than the
external volume of said first hollow totally enclosed structure..].
.[.9. A structure defined according to claim 1 wherein (i) said
base portion comprises a first thin polymer shell having a curved
surface and an inner void portion and an inner surface and an outer
surface and a first sealable continuous circumferential edge; (ii)
said upper portion comprises a second thin shell section having a
second sealable continuous circumferential edge which substantially
conforms in shape to said first sealable circumferential edge and
(iii) said base portion is sealed by means of a continuous seal at
the said first circumferential edge thereof to said upper portion
at the said second circumferential edge thereof..]. .[.10. A
structure defined according to claim 2 wherein (i) said base
portion comprises a first thin polymer shell having a curved
surface and an inner void portion and an inner surface and an outer
surface and a first sealable continuous circumferential edge; (ii)
said upper portion comprises a second thin shell section having a
second sealable continuous circumferential edge which substantially
conforms in shape to said first sealable circumferential edge and
(iii) said base portion is sealed by means of a continuous seal at
the said first circumferential edge thereof to said upper portion
at the said second circumferential edge thereof..]. .[.11. A
structure defined according to claim 3 wherein (i) said base
portion comprises a first thin polymer shell having a curved
surface and an inner void portion and an inner surface and an outer
surface and a first sealable continuous circumferential edge; (ii)
said upper portion comprises a second thin shell section having a
second sealable continuous circumferential edge which substantially
conforms in shape to said first sealable circumferential edge and
(iii) said base portion is sealed by means of a continuous seal at
the said first circumferential edge thereof to said upper portion
at the said second circumferential edge thereof..]. .[.12. The
structure claimed according to claim 1 wherein the driving force of
the molecular mass transfer of the volatile substance from within
the hollow totally enclosed structure to the atmosphere surrounding
said structure on operation thereof results from (a) a difference
in the pressure between the gas phase of the inner void of said
shell and the gas phase-containing 3-space immediately adjacent the
outer surface of said microporous polymer shell section and (b) the
steady state desorption of the liquid phase of the volatile
substance present in the microporous polymer into the gas
phase-containing 3-space immediately adjacent the outer surface of
said microporous polymer shell section and (c) the steady state
absorption of the liquid phase of volatile substance present in a
microporous polymer from the gas phase within the inner void of
said shell onto the inner surface of said microporous polymer shell
section..]. .[.13. A plurality of hollow totally enclosed
structures laterally and detachably interconnected having a common
midplane, each of said structures being defined individually
according to claim 9, each of said structures connected to at least
one other of said structures (i) at a location midway between the
base portion of each of said structures and the upper portion of
each of said structures and (ii) along at least a portion of the
circumferential sealed edge of each of said individual structures
sealing said upper portion to said base portion of each of said
individual hollow totally enclosed structures..]. .[.14. A
plurality of hollow totally enclosed structures laterally and
detachably interconnected having a common midplane, each of said
structures being defined individually according to claim 10, each
of said structures connected to at least one other of said
structures (i) at a location midway between the base portion of
each of said structures and the upper portion of each of said
structures and (ii) along at least a portion of the circumferential
sealed edge of each of said individual structures sealing said
upper portion to said base portion of each of said individual
hollow totally enclosed structures..]. .[.15. A plurality of hollow
totally enclosed structures laterally and detachably interconnected
having a common midplane, each of said structures being defined
individually according to claim 11, each of said structures
connected to at least one other of said structures (i) at a
location midway between the base portion of each of said structures
and the upper portion of each of said structures and (ii) along at
least a portion of the circumferential sealed edge of each of said
individual structures sealing said upper portion to said base
portion of each of said individual hollow totally enclosed
structures..]. .[.16. A process for controllably dispensing at a
visibly detectable rate continuously or discontinuously for
discrete periods of time a volatile composition of matter from a
container into the atmosphere surrounding said container which
process comprises the steps of:
(a) entrapping the volatile composition of matter in an entrapment
agent whereby a temporarily entrapped volatile composition is
formed;
(b) providing a first thin shell section composed of a thin polymer
shell having a curved surface and having an inner void portion, an
inner surface and an outer surface and having a first continuous
sealable circumferential outer edge and a first geometric
configuration;
(c) placing the entrapped volatile composition in the inner void
portion of said first thin shell section and onto the inner surface
of said first thin shell section, said volatile composition being
selected from the group consisting of perfume compositions,
herbicide compositions, insecticide compositions, animal repellant
compositions, air freshener compositions, pheremone compositions,
odor maskant compositions, deodorant compositions and insect
repellent compositions;
(d) providing a second thin shell section having a second sealable
circumferential edge and having a shape and volume which are such
that when said second shell is placed in conforming adjacent
edgewise contact with said first shell, a totally enclosed shell
structure is produced with said entrapped volatile composition
being totally enclosed within said shell section;
(e) placing said second thin shell section having said second
sealable circumferential continuous edge which substantially
conforms in shape to said first sealable circumferential edge onto
said first thin shell section whereby said first sealable edge is
in closely fitting sealable proximity with said second
circumferential edge; and
(f) sealing said first sealable edge to said second sealable edge
whereby the resulting shell structure enclosing said entrapped
volatile composition is totally enclosed and substantially
air-tight with the exception of ingress and egress of volatile
composition molecules controllably and at a constant velocity
through the polymer wall during functional operation of the
resulting shell structure;
at least a finite section of said first thin shell section or said
second thin shell section comprising a microporous polymer having a
porosity such that when said hollow totally enclosed structure thus
formed is located in an inert gas at a pressure of less than or
equal to about 1 atmosphere, said volatile material molecules are
transported at a constant linear velocity and at a total derivative
of concentration of volatile substance with respect to time onto
the inner surface of said microporous polymer section via an
adsorption mechanism and from the outer surface of said
microporous polymer section via a desorption mechanism..]. .[.17.
The process of claim 16 wherein the first thin shell section is
composed of a non-porous and transparent polymer and said second
thin shell section is a microporous polymeric membrane and is
opaque at least at the instant in time of commencement of the
functional operation of said structure, said microporous polymer
membrane containing solid particles having an average particle
diameter of from about 0.3 up to about 500 microns..]. .[.18. The
process of claim 16 comprising the additional step (g) of placing
the resulting shell structure when not in use into an outer
all-enclosing container which outer container is non-porous and is
composed of a material which prevents the volatile material
molecules from being transported or diffusing therethrough, the
dimensions of the outer container being such that the volume of
said outer container and the shape of said outer container are such
that the outer container totally encloses the inner container, said
outer container having a sealable entrance therein whereby the
shell structure defined according to claim 16 may be placed into
and removed from said outer container and whereby said outer
container may be sealed in an air-tight manner after the placing of
said shell structure of claim 16 into said outer container..].
.[.19. The process of claim 16 wherein the volatile composition of
matter entrapped in the entrapment agent is placed in a plurality
of hollow totally enclosed structures which are laterally and
detachably interconnected and which have a common midplane, each of
said structures connected to at least one other of said structures
(i) at a location midway between the base portion of each of said
structures and the upper portion of each of said structures and
(ii) along at least a portion of the circumferential sealed edge of
each of said individual structures sealing said upper portion to
said base portion of each of said individual hollow totally
enclosed structures..]. .[.20. The hollow totally enclosed
structure of claim 1 which is in the shape of a cylinder, the ends
of the cylinder being microporous and the side of said cylinder
being non-porous to said volatilizable composition of matter, at
least a finite portion of the side
of said cylinder being translucent..]. .Iadd.21. A hollow totally
enclosed structure comprising a thin shell totally enclosing an
inner void, said thin shell having a base portion and an upper
portion, said base portion having an inner surface:
(i) at least a finite portion of said thin shell being transparent
whereby that portion of said inner void which is located proximate
to the base portion of said totally enclosed structure is visible
from without said thin shell, in the presence of visible
wave-lengths of light;
(ii) contained totally within the said inner void of said thin
shell and in place on said inner surface of said base portion, a
volatile composition temporarily entrapped and totally entrapped at
least at the instant in time of commencement of functional
operation of said structure, in a gelatinous entrapment material,
said volatile composition being selected from the group consisting
of perfume compositions, herbicide compositions, insecticide
compositions, animal repellent compositions, air freshener
compositions, pheromone compositions, odor maskant compositions,
deodorant compositions and insect repellent compositions, said
gelatinous entrapment material containing said volatile composition
having an upper surface;
(iii) at least a finite section of said upper portion of said thin
shell comprising a microporous polymer and termed "a microporous
polymer shell section" having a porosity such that when said hollow
totally enclosed structure is located in an inert gas at a pressure
of less than or equal to about 1 atmosphere, said volatile material
molecule are transported at a constant linear velocity and at a
constant total derivative of concentration of volatile substance
with respect to time onto the inner surface of said microporous
polymer section via an adsorption mechanism and from the outer
surface of said microporous polymer section to the surrounding
atmosphere via a desorption mechanism, said microporous polymer
shell section consisting essentially of a polyolefin intimately
admixed with a powder having an average particle diameter of from
about 0.3 up to about 500 microns, said powder being a filler
material incompatible with said polymer, said powder being in a
proportion of about 5 to 100 parts by weight per 100 parts by
weight of polymer, the said volatile composition having a
volatility at ambient conditions which is higher than the
transmissibility of said microporous polymer shell section,
the volume of said gelatinous entrapment material being
substantially less than the volume of said inner void, there
existing at least one substantial void space between (i) said upper
surface of said gelatinous entrapment material containing said
volatile composition and (ii) said
upper portion of said thin shell. .Iaddend. .Iadd.22. The hollow
totally enclosed structure of claim 21 wherein the thickness of the
microporous polymeric section is about 100 microns; the pore size
is approximately 0.2 microns; the void volume of the microporous
polymer section is approximately 34 cubic centimeters per gram and
the density of the microporous polymer section is approximately 900
kilograms per cubic meter. .Iaddend. .Iadd.23. A structure
comprising:
(a) a first hollow totally enclosed structure comprising a thin
shell totally enclosing an inner void, said thin shell having a
base portion and an upper portion, said base portion having an
inner surface:
(i) at least a finite portion of said thin shell being transparent
whereby that portion of said inner void which is located proximate
to the base portion of said totally enclosed structure is visible
from without said thin shell, in the presence of visible
wave-lengths of light;
(ii) contained totally within the said inner void of said thin
shell and in place on said inner surface of said base portion, a
volatile composition temporarily entrapped and totally entrapped at
least at the instant in time of commencement of functional
operation of said structure, in a gelatinous entrapment material,
said volatile composition being selected from the group consisting
of perfume compositions, herbicide compositions, insecticide
compositions, animal repellent compositions, air freshener
compositions, pheromone compositions, odor maskant compositions,
deodorant compositions and insect repellent compositions, said
gelatinous entrapment material containing said volatile composition
having an upper surface;
(iii) at least a finite section of said upper portion of said thin
shell comprising a microporous polymer and termed "a microporous
polymer shell section" having a porosity such that when said hollow
totally enclosed structure is located in an inert gas at a pressure
of less than or equal to about 1 atmosphere, said volatile material
molecule are transported at a constant linear velocity and at a
constant total derivative of concentration of volatile substance
with respect to time onto the inner surface of said microporous
polymer section via an adsorption mechanism and from the outer
surface of said microporous polymer section to the surrounding
atmosphere via a desorption mechanism, said microporous polymer
shell section consisting essentially of a polyolefin intimately
admixed with a powder having an average particle diameter of from
about 0.3 up to about 500 microns, said powder being a filler
material incompatible with said polymer, said powder being in a
proportion of about 5 to 100 parts by weight per 100 parts by
weight of polymer, the said volatile composition having a
volatility at ambient conditions which is higher than the
transmissibility of said microporous polymer shell section and
enclosing said first structure;
(b) a second air-tight totally enclosed structure, said first
totally enclosed structure having a volume less than said second
air-tight totally enclosed structure, said first totally enclosed
structure being of such dimensions that it is (i) enclosable within
said second air-tight totally enclosed hollow structure, and (ii)
the internal volume of said second air-tight totally enclosed
hollow structure is greater than the external volume of said first
hollow totally enclosed structure,
the volume of the gelatinous entrapment agent being substantially
less than the volume of said inner void, there existing at least
one substantial void space between (i) said upper surface of said
gelatinous entrapment material containing said volatile composition
and (ii) said upper portion
of said thin shell. .Iaddend. .Iadd.24. A plurality of hollow
totally enclosed structures laterally and detachably interconnected
having a common midplane, each of said structures individually
being a hollow totally enclosed structure comprising a thin shell
totally enclosing an inner void, said thin shell having a base
portion and an upper portion, said base portion having an inner
surface:
(i) at least a finite portion of said thin shell being transparent
whereby that portion of said inner void which is located proximate
to the base portion of said totally enclosed structure is visible
from without said thin shell, in the presence of visible
wave-lengths of light;
(ii) contained totally within said inner void of said thin shell
and in place on said inner surface of said base portion, a volatile
composition temporarily entrapped and totally entrapped at least at
the instant in time of commencement of functional operation of said
structure, in a gelatinous entrapment material, said volatile
composition being selected from the group consisting of perfume
compositions, herbicide compositions, insecticide compositions,
animal repellent compositions, air freshener compositions,
pheromone compositions, odor maskant compositions, deodorant
compositions and insect repellent compositions, said gelatinous
entrapment material containing said volatile composition having an
upper surface;
(iii) at least a finite section of said upper portion of said thin
shell comprising a microporous polymer and termed "a microporous
polymer shell section" having a porosity such that when said hollow
totally enclosed structure is located in an inert gas at a pressure
or less than or equal to about 1 atmosphere, said volatile material
molecule are transported at a constant linear velocity and at a
constant total derivative of concentration of volatile substance
with respect to time onto the inner surface of said microporous
polymer section via an adsorption mechanism and from the outer
surface of said microporous polymer section to the surrounding
atmosphere via a desorption mechanism, said microporous polymer
shell section consisting essentially of a polyolefin intimately
admixed with a powder having an average particle diameter of from
about 0.3 up to about 500 microns, said powder being a filler
material incompatible with said polymer, said powder being in a
proportion of about 5 to 100 parts by weight per 100 parts by
weight of polymer, the said volatile composition having a
volatility at ambient conditions which is higher than the
transmissibility of said microporous polymer shell section, each of
said structures connected to at least one other of said structures
(i) at a location midway between the base portion of each of said
structures and the upper portion of each of said structures and
(ii) along at least a portion of the circumferential sealed edge of
each of said individual structures sealing said upper portion to
said base portion of each of said individual hollow totally
enclosed structures,
the volume of the gelatinous entrapment agent being substantially
less than the volume of said inner void, there existing at least
one substantial void space between (i) said upper surface of said
gelatinous entrapment material containing said volatile composition
and (ii) said upper portion of said thin shell. .Iaddend. .Iadd.25.
A process for controllably dispensing continuously or
discontinuously for discrete periods of time a volatile composition
of matter from a container into the atmosphere surrounding said
container, said container consisting of two oppositely
coincidentally sealably fitting thin concave polymeric shells at
least a finite portion of at least one of said shells comprising a
microporous polymer wall section which process comprises the steps
of:
(a) entrapping the volatile composition of matter in a gelatinous
entrapment material whereby a temporarily entrapped volatile
composition is formed;
(b) providing a first thin shell section composed of a thin polymer
shell having a curved surface and having an inner void portion, an
inner surface and an outer surface and having a first continuous
sealable circumferential outer edge and a first geometric
configuration;
(c) placing the entrapped volatile composition in the inner void
portion of said first thin shell section and onto the inner surface
of said first thin shell section, said volatile composition being
selected from the group consisting of perfume compositions,
herbicide compositions, insecticide compositions, animal repellent
compositions, air freshener compositions, pheromone compositions,
odor maskant compositions, deodorant compositions and insect
repellent compositions, said gelatinous entrapment material
containing said volatile composition having an upper surface;
(d) providing a second thin shell section having a second sealable
circumferential edge and having a shape and volume which are such
that when said second shell is placed in conforming adjacent
edgewise contact with said first shell, a totally enclosed shell
structure is produced with said entrapped volatile composition
being totally enclosed within said shell section;
(e) placing said second thin shell section having said second
sealable circumferential continuous edge which substantially
conforms in shape to said first sealable circumferential edge onto
said first thin shell section whereby said first sealable edge is
in closely fitting sealable proximity with said second
circumferential edge, whereby there exists at least one substantial
void space between (i) said upper surface of said gelatinous
entrapment material containing said volatile composition and (ii)
said upper portion of said thin shell;
(f) sealing said first sealable edge to said second sealable edge
whereby the resulting shell structure enclosing said entrapped
volatile composition is totally enclosed and substantially
air-tight with the exception of ingress and egress of volatile
composition molecules controllably and at a constant velocity
through said second thin shell section during functional operation
of the resulting shell structure, at least a finite section of said
second thin shell section being a microporous polymer section
having a porosity such that when said hollow totally enclosed
structure thus formed is located in an inert gas at a pressure of
less than or equal to about 1 atmosphere, said volatile material
molecules are transported at a constant linear velocity and at a
total derivative of concentration of volatile substance with
respect to time onto the inner surface of said microporous polymer
section via an adsorption mechanism and from the outer surface of
said microporous polymer section via a desorption mechanism, said
microporous polymer section containing solid particles selected
from the group consisting of talc and calcium carbonate having an
average diameter of from about 0.3 up to about 500 microns, in a
proportion of from about 5 to 100 parts by weight of polymer.
.Iaddend.
Description
BACKGROUND OF THE INVENTION
Our invention provides volatile substance-emitting apparatus and
methods for producing same and for using same wherein the volatile
substance can be an air freshener, standard aromatizing material,
odor maskants, insecticides, insect repellants, animal repellants,
herbicies, 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 order", that is, a function of the
concentration previously present, e.g.: ##EQU1##
Furthermore, 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 instances it is impossible to
determine precisely when the volatile substance is no longer being
discharged in an effective quantity and/or concentration per unit
time into the atmosphere surrounding the container. In those
situations where an aroma is being emitted, the actual aroma is
usually relatively powerful during the emission notwithstanding the
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 Pat. No. J8-0036,515 assigned to Akane Soji K K,
printings from which fragrance is gradually emitted are indicated
to be produced by a process comprising (1) preparing
fragrance-emitting ink compositions by dispersing (a)
fragrance-emitting bases prepared by mixing perfume solutions with
thermoplastic resins at elevated 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 ink composition.
Scent-releasing polyurethane foams are shown to be prepared in
German published Application No. 2,945,757 (assigned to the Tenneco
Chemical, Inc.). In published Application No. 2,945,757, it is
indicated that a polyurethane foam containing a particulate filler
and perfume is prepared by first mixing the filler with the perfume
and adding this mixture 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. Pat. No. 4,226,944 issued on
Oct. 7, 1980.
U.S. Pat. No. 4,247,498 issued on Jan. 27, 1981 discloses a method
for preparing a homogeneous 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. Pat. No.
4,247,498 comprises (i) heating a mixture of a polymer which may be
an olefinic polymer, condensation polymer, oxidation polymer or a
blend thereof and a "compatible liquid" to a temperature and for a
time sufficient 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
cooling 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. Pat. No.
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 21/3 inches".
Japanese published Application No. J5-5081,655 assigned to Kureha
Chemical Industries KK discloses a slow release air aromatizing
composition which comprises an aqueous solution of water soluble
high molecular weight substance of viscosity 500-30,000 cps such as
polyvinyl acetate, carboxymethyl cellulose, sodium alginate,
xanthan gum, etc. admixed with 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.
OBJECTS OF THE INVENTION
It is an object of our invention to provide a process for
dispensing at a controllable, visibly detectable rate, continuously
or discontinuously 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 a 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 who views the inner void of the apparatus which is
instrumental in carrying out the process.
SUMMARY OF THE INVENTION
Our invention defines a process for dispensing in a controllable
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 comprising a thin shell totally
enclosing an inner void, the thin shell having a base portion and
an upper portion, 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 light;
(ii) contained totally within 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 package);
and
(iii) at least a finite section of the thin shell comprising a
microporous polymer (preferably containing a plurality of finite
solid particles) having a porosity such that when the hollow
totally enclosed structure is located in an inert gas at a pressure
less than or equal to about 1 atmosphere, the volatile material
molecules (e.g., the perfume molecules or the air freshener
molecules) are adsorbed onto the inner surface of the microporous
polymer section and desorbed from the outer surface of the
microporous polymer section at a constant linear velocity and at
constant total derivative of concentration of volatile substance
within said thin shell with respect to time through the microporous
polymer section.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a preferred embodiment of the
hollow totally enclosed structure of our invention, with the
material of fabrication being flexible polypropylene film.
FIG. 2 is an elevation view of the hollow totally enclosed
structure of FIG. 1 shown in cross section with the structure fully
loaded with temporarily-entrapped volatile substance.
FIG. 3 is a partial cut-away plan view of the structure of FIG. 1
with the structure fully loaded with volatile substance immediately
prior to functional use thereof.
FIG. 4 is a side view of the structure of FIG. 1 shown in cross
section with the volatile substance completely spent.
FIG. 5 is a perspective view of a second preferred embodiment of
the structure in accordance with our invention with a hollow
cylinder fully loaded immediately prior to functional use
thereof.
FIG. 6 is an elevation view of the apparatus of FIG. 1 shown in
cross section fully loaded with volatile substance immediately
prior to functional use thereof, the structure being located within
an outer larger air-tight structure, the apparatus containing the
entrapped volatile substance not being in functional use.
FIG. 7 is an elevation view of the cylindrical apparatus of FIG. 5
shown in cross section, with the volatile substance being fully
loaded in said structure of FIG. 5, the structure of FIG. 5
contained in a larger enclosing cylinder which is air-tight whereby
the structure of FIG. 5 is not in functional use.
FIG. 8 is an elevation view of the apparatus of FIG. 5 shown in
cross section with the volatile substance previously contained in
the cylindrical structure having been fully depleted.
FIG. 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.
FIG. 10 is an elevation view of the structure of FIG. 9 shown in
cross section with the entrapped volatile substance previously
contained in said structure having been fully spent.
FIG. 11 is a perspective view of a structure in accordance with our
invention where multiple structures (as the individual structure of
FIG. 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.
FIG. 12 is an elevation view of the structure of FIG. 11 shown in
cross section with each of the individual structures of the
inter-connected plurality of structures being fully loaded with
volatile substance immediately prior to functional use thereof.
FIG. 13 is an elevation view of the apparatus of FIG. 11 shown in
cross section with each of the interconnected structures of the
structure of FIG. 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.
FIG. 14 is a plan view of the plurality of inter-connected
structures of FIG. 11.
FIG. 15 is an elevation view of the structure of FIG. 11 which is
actually a plurality of inter-connected structures (as the
individual structure of FIG. 1), with each of the individual
structures containing spent volatile substances immediately
subsequent to the last functional use of said structure.
FIG. 16 is a perspective cross-sectional view of the structure of
FIG. 11 rolled up and placed in an air-tight cylindrical
outer-container when not being used.
FIG. 17 is a perspective view of another preferred embodiment of
our invention wherein a plurality of hollow totally enclosed
structures are laterally and detachably inter-connected and have a
common midplane with each of said structures being connected to at
least two other of said structures at a location midway between 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 FIG. 17, the shape of the individual structures is
"heart"-shaped rather than ellipsoidal in shape.
FIG. 18 is a series of graphs of percent volatiles lost versus time
comparing the functional use of structures as illustrated in FIG. 1
containing temporarily-entrapped volatilizable substance (air
freshener), not containing volatilizable substance (but replaced by
ethanol, per se) and standard commercial air fresheners of the
prior art as defined according to U.S. Pat. No. 4,014,501. The
graphs are more particularly described in Examples I and II,
infra.
FIG. 19 is a comparative graph showing percent fragrance loss
versus time for a structure containing air freshener-containing
volatilizable substance as set forth in FIG. 1 versus the same
volatilizable substance (air freshener contained in a gel) in the
absence of said structure of our invention. (The graph is more
particularly described in Example III, infra.)
FIG. 20 represents a graph of rate of fragrance loss versus time
for the structure of FIG. 1 for up to one month of use.
FIG. 21 represents an operational graph of rate of fragrance loss
versus time for a structure as shown in FIG. 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. FIG. 21
indicates three separate use (followed by storage) periods for the
structure of FIG. 6
FIG. 22 represents a graph of rate of fragrance loss versus time
for the entire period of possible continuous use of the structure
of FIG. 1 assuming that the structure of FIG. 1 is not replaced at
discrete time intervals in an enclosed air-tight outer
container.
DETAILED DESCRIPTION OF THE INVENTION
The process of our invention comprises dispensing at a visibly
detectable rate continuously (as illustrated in FIG. 20) or
discontinuously for discrete periods of time (as shown in FIG. 21)
at steady state, a volatile composition of matter 3 from a
container, e.g., as represented by reference numeral 500 in FIG. 1,
into the atmosphere surrounding said container. The steps of this
process are examplified using structure 500 as follows:
(a) entrapping a volatile composition of matter which may be a
perfume composition, an air freshening composition, a deodorizing
composition, an animal repellant composition, an insect repellant
composition, an insecticide, a herbicide or a pheremone composition
or the like, in an entrapment agent whereby a temporarily entrapped
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 thin 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 circumferential
edge, a totally enclosed shell structure 500 is produced with said
entrapped volatile composition 3 being totally enclosed within said
shell structure leaving a void 6 between said second thin shell
section 2 and said volatile substance 3;
(e) placing said second thin shell section 2 having a second
sealable continuous circumferential edge which substantially
conforms in shape to said first sealable circumferential edge onto
said first thin shell section 4 whereby said first sealable edge is
in closely fitting sealable proximity with said second sealable
edge at location 1;
(f) sealing said first sealable edge to said second sealable edge
at location 1 whereby the resultant 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 insert gas at a pressure of less than or
equal to about 1 atmosphere, said volatile material molecules
diffuse at a constant linear velocity and at a constant total
derivative of concentration of volatile substance with respect to
time through said microporous 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 container 7
is air-tight. The outer container 7 prevents the escape of the
volatile substance from the entrapment medium into the atmosphere
prior to the desired operation of the shell 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 partially transparent.
Examples of the aforesaid microporous polymer compositions of
matter are as follows:
(a) Microporous polymers .[.prepared, for example, according to
Canadian Pat. Nos. 1,021,916 or 1,039,911 and U.K. Pat. No.
1,414,785.]. manufactured by Koninklijke Emballage Industrie Van
Leer B.V. of Amstelveen, The Netherlands, .[.the disclosures of
which patents are incorporated by reference herein.]. for example,
a microporous film containing talc having the following
specification:
______________________________________ Composition Polypropylene +
filler Thickness 100 .+-. .[.milli.]. microns Weight .+-.90
g/m.sup.2 Ultimate tensile 30 MN/m.sup.2 (machine strength
direction) 11 MN/m.sup.2 (transverse direction) Elongation at break
180% (machine direction) 350% (transverse direction) Pore size 0.2
.[.milli.]. microns.[.(mas).]. .Iadd.(max).Iaddend. Void volume .34
cm.sup.3 /g (30%) Density .+-.900 kg/m.sup.2 Air flow 3 cm.sup.3
/cm.sup.2 /min at 1 kg/cm.sup.2 Water flow 0.001 cm.sup.3 /cm.sup.2
/min at 1 kg/ cm.sup.2 Air resistance (Gurley) 10.sup.4 secs. Water
vapour trans- 150 g/m.sup.2 /24 hrs at 23.degree. C. mission 50% rh
Thermal stability 10 hrs at 130.degree. C.
______________________________________
.[.(b) Thin microporous films produced from Surlyn.RTM. resin as
described in Examples 362, 363, 364, 365 and 366 at columns 45 and
46 of U.S. Pat. No. 4,247,498 the disclosure of which patent is
incorporated by reference herein;.].
.[.(c) A microporous polymer membrane produced according to Example
10 of U.S. Pat. No. 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 FIG. 2; or 11 in FIG. 5; or 19 in FIG. 9;B.].
.[.(c-bis) A microporous polymer prepared according to U.S. Pat.
No. 4,239,714, the abstract for which is set forth below:.].
.[.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 entraces to the pores..].
.[.A conc. soln of a pore blocking agent is applied to the bulk
surface of (I). The pore blocking agent 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
insolubilised 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
electrodialysis, electrophoresis or gel permeation or gel exclusion
chromatography..].
.[.(d) A membrane produced according to Japanese Application No.
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
No. J5-5078,965 assigned to Kokando KK and published on June 14,
1980;.].
.[.(f) A microporous polyurethane specifically as described in
German Offenlegungsschrift No. 2,324,314 published on Nov. 29, 1973
and assigned to Teijin Cordley Ltd. (abstracted in Chem. Abstracts
Volume 81, 1974 at section 4589u)..].
Insofar as the microporous film is concerned, it is preferred that
a filler be incorporated therein having 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 or
sodium alkyl naphthalene sulphonate. Where the sulphonate used is
an alkyl benzene sulphonate, the benzene ring of the sulphonate
preferably has only 1 allyl substituent and such substituent
contains from 8 to 18 carbon atoms. Among such alkyl benzene
sulphonates are sodium linear dodecylbenzene sulphonate, sodium
tridecylbenzene sulphonate and sodium nonylbenzene sulphonate. On
the other hand, where the sulphonate used is an alkyl naphthalene
sulphonate, the naphthalene ring of the sulphonate perferably 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 monoisopropylnaphthalene sulphonate, sodium
diisopropylnaphthalene sulphonate, sodium diamylnaphthalene
sulphonate and sodium monocaprylnaphthalene sulphonate. The
sulphonates in solid form are commercially available in 40% to 90%
by weight 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
commercially, but other forms can also be used.
Useful clay fillers are described in U.S. Pat. No. 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, hexamethylene diamine, tetraethylene diamine,
diethylene triamine, tetraethylene pentamine and guanidine.
Other useful clay fillers are described in U.S. Pat. No. 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 sulphonate, 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
entrapping the aromatizing substance used or absorb the aromatizing
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.
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 5 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 microporous polymer or polymer or other
substance used in fabricating the outer shell of the structure of
our invention. Fragrances are usually complex 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 U.S.
Pat. No. 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, polyphenylene 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-liquid phase separation
and form 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 (Naperian base) 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 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 polymer
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 any convenient area or 3-space. FIG. 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 FIG. 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 interconnected as
shown in FIGS. 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 common
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 FIG. 12, to wit: the upper portions as 23C, 23D
and 23J and the lower portions shown as 29C, 29D and 29J.
In constructing such a structure as structure 504 in FIGS. 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 containing such lower portions as 29C, 29D
and 29J at sealable circumferential 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 26C, 26D and 26J being through microporous polymer
sections in upper shell portions 23C, 23D, 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 FIGS. 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 FIG. 13 or they may be rolled up and stored in container
505 as illustrated in FIG. 16. Conveniently, the container 505 in
FIG. 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. When
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, 26D and 26J takes
place into the outer atmosphere.
After 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 FIG. .[.16.].
.Iadd.15 .Iaddend.(as reference numerals 28C, 28D and 28J). Thusly,
the void 27C, 27D and 27J is fully visible from 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.
FIG. 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 508.
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.S.
Pat. No. 4,014,501) is set forth in FIG. 18. The graphs shown by
reference numerals 201 and 203 represent the operation of structure
500 (percent volatile substance loss versus time) without any
perfume material contained within the entrapped volatile substance
3 .[.buy.]. .Iadd.but .Iaddend.only containing ethyl alcohol
entrapped in gel 3. The graphs shown by reference numerals 202 and
204 (percent perfume 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 numbers 201, 202, 203 and 204
being that described in Canadian Pat. Nos. 1,039,911 and 1,021,916
and U.K. Pat. No. 1,414,785 whereby.]. specially compounded
polypropylene film with talc is used, having the following
specifications:
______________________________________ Composition Polypropylene +
filler Thickness 100 .+-. .[.milli.]. microns Weight .+-.90
g/m.sup.2 Ultimate tensile 30 MN/m.sup.2 (machine strength
direction) 11 MN/m.sup.2 (transverse direction) Elongation at break
180% (machine direction) 350% (transverse direction) Pore size 0.2
.[.milli.]. microns (max) Void volume .34 cm.sup.3 /g (30%) Density
.+-.900 kg/m.sup.2 Air flow 3 cm.sup.3 /cm.sup.2 /min at 1
kg/cm.sup.2 Water flow 0.001 cm.sup.3 /cm.sup.2 /min at 1 kg/
cm.sup.2 Air resistance (Gurley) 10.sup.4 secs. Water vapour trans-
150 g/m.sup.2 /24 hrs at 23.degree. C. mission 50% rh
______________________________________
as manufactured by Koninklijke Emballage Industrie Van Leer B.V. of
Amstelveen, The Netherlands.
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 "0" order, that is: ##EQU2##
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 FIG. 18 are prepared is set forth in Examples I and II,
infra.
By the same token, in FIG. 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:
##EQU3##
On the other hand, the graph indicated by reference numeral 301 in
FIG. 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
FIGS. 1, 2 and 3. The depleted air freshener gel is shown by
reference numeral 5 in FIG. 4 (the depletion being at the end of a
55 day period as shown on the graph indicated by reference numberal
301 in FIG. 19).
FIGS. 20 and 21 show, respectively, continuous and discrete usages
of the shell structure as illustrated in FIG. 1. FIG. 20 is a graph
of (dc/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 (dc/dt) is a
constant for at least one month (until depletion as shown in FIGS.
4 and 8).
In FIG. 21, (dc/dt) is a constant after the first five minutes of
usage until the time that the shell structure of our invention as
shown in FIG. 1 is placed into an outer container as shown in any
one of FIGS. 6, 7 or 16.
FIG. 22 is a graph of (dc/dt) versus time wherein the period of
from t.sub.0 '" to t.sub.1 '" is a condition of "unsteady state"
mass transport (usually no more than a few minutes) and the period
from t.sub.1 '" to t.sub..omega. '" 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 microporous polymer section
of the shell structure of our invention may be set forth in the
form of a mathematical model as taught by Adamson "Physical
Chemistry of Surfaces" Second Edition, Interscience Publishers,
1967, as follows: ##EQU4## 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"; "K" being indicative of
equilibrium constant and
representing the sum total of the moles on the adsorbed layer.
Another embodiment 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 FIGS. 5, 7, 8, 9 and 10.
The process of our invention for dispensing at a controllable and
visibly detectable rate, continuously or discontinuously, for
discrete periods of time a volatile composition of matter from a
cylindrical container 501 into the atmosphere surrounding the
container in this particular embodiment 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
composition 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 transparent 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 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 FIG.
8). The side wall of the cylinder 12 may be fabricated from a
microporous polymer .[.such as that described in Canadian Pat. No.
1,039,911 or United Kingdom Pat. No. 1,414,785 assigned to
Koninklijke Emballage Industrie Van Leer B.V. or can be produced of
microporous polymers which are laminated such as that described in
Israel Pat. No. 52650 assigned to Koninklijke Emballage Industrie
Van Leer B.V..]. wherein, for example, the polymer .[.is
microporous and.]. contains a talc filler.
When not in use, the cylinder 501 containing entrapped volatile
substance 11 is preferably placed in an outer cylindrical container
502 as shown in FIG. 7. The outer cylindrical container is referred
to by reference numeral 502 in FIG. 7. The outer cylindrical
container has a removable cap 14 which may be screwed at 103 into
the lower portion 13 of said outer container 502. When the cylinder
15 is in use, the screw top 14 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, merely the upper third
or the upper quarter or the lower quarter of the side wall or even
the top or the bottom of the cylindrical container may be
fabricated from microporous 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.
Another embodiment of the cylindrical hollow structure which is
illustrative of our invention is set forth in FIGS. 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 threads
20. Thus, structure 503 containing volatile substance 19 may be
manufactured in a form which is reusable when the volatile
substance 19 is depleted down to the remaining depleted gel (or
other entrapment substance) 21 as indicated in FIG. 10.
Conveniently, lower portion 18 may be fabricated from a transparent
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 FIG. 10), the upper portion 17 of cylinder 503 in
FIGS. 9 and 10 may be temporarily removed and additional substance
19 may be added to the lower portion 18. Structure 503 in FIGS. 9
and 10 may then be replaced into a larger cylinder to form a
structure such as that illustrated in FIG. 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, although the general mass transport
equation is: ##EQU5## wherein N.sub.A is the molar rate of mass
transport per unit area; D.sub.AB is the "diffusivity" of A in B, a
physical property of the volatile vapor and the adsorbing polymer,
C.sub.A is the molar concentration of A in the void space
immediately within the shell; and y is the thickness of the
adsorbing and desorbing polymer. For the purpose of our invention
N.sub.A 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: ##EQU6##
wherein (.differential.C.sub.A /.differential.t) is a constant.
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
FIGS. 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.
EXAMPLE I
Into compartment 6, onto surface 4 of the structure 500 illustrated
in FIGS. 1, 2 and 3 is placed a composition prepared as follows:
3.0 parts by weight of Carbopol .RTM. 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 paraben. The mixing is continued until a smooth
cloudy dispersion is formed. 2.0 parts by weight of a perfume
composition (see Note 2) is added to the prepared slurry 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 diisopropanolamine (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 FIGS. 1, 2 and
3 and use of the structure resulting therefrom is shown in
accordance with the graph referenced by reference numeral 202 in
FIG. 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 FIG. 18. It will be noted that for periods of use, structure
500 operates at steady state very soon after (5 minutes) use is
commenced.
______________________________________ Ingredients Parts by Weight
______________________________________ Para cresol 1 Methyl
jasmonate 100 Acetyl methyl anthranilate 20 Farnesol 4
Cis-3-hexenyl benzoate 30 Nerolidol 30 Indol 15 Eugenol 20 Benzyl
alcohol 40 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 entrapped volatile substance 3 is 30 grams.
EXAMPLE II
3.0 parts by weight of Carbopol .RTM. 940 (manufactured by the B.
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 mixing to
avoid inclusion of air. The resulting gel is then placed into
cylinder 501 of FIG. 5. The use of this air freshener cylinder is
in accordance with the graph indicated by reference numeral 204 in
FIG. 18. Without the use of the perfume composition of Example I,
the cylindrical shell of FIG. 5 operates in accordance with the
graph indicated by reference numeral 203 in FIG. 18. In both cases,
the percent volatiles lost during Example I (but using ethanol,
instead), the cylindrical shell of FIG. 5 operates in accordance
with the graph indicated by reference numeral 203 in FIG. 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
FIG. 18.
When the gel of this example is simply used in a commercial air
freshener (in the air freshener of U.S. Pat. No. 4,014,501), the
mass transport mechanism is "unsteady state" in accordance with the
graph indicated by reference numeral 205 in FIG. 18.
EXAMPLE III
83.45 grams of distilled water is heated to 85.degree. C. With
rapid agitation on a propeller type mixer, Gelcarin .RTM. AFG-15
(carageenan prepared by the Marine Colloids Corporation) is
dispersed in the water. 3.50 grams of glycerine is slowly added to
the carageenan dispersion. The mixture of glycerine 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
.RTM. 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 FIG. 9. It is material is then poured into lower portion 18 of
cylinder 503 of FIG. 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 package (per U.S. Pat. No. 4,014,501), the
rate of fragrance loss is shown in accordance with the graph
indicated using reference numeral 302 in FIG. 19 (an unsteady state
mass transport mechanism rather than the steady state mass
transport mechanism of graph 301 in FIG. 19).
* * * * *