Note: Descriptions are shown in the official language in which they were submitted.
Back~round of the Invention
The present invention relates to the chemical
sterilization process ~or articles such as contact lenses.
More particularly, this invention concerns an improved method
of chemical sterilization and apparatus adapted to be employed
with said improved method, or with other types of similar
chemical processes wherein a chemical reaction is to be delayed
for a specified period of time.
The present invention evolved with regard to
sterilization techniques for contact lenses, and will be
described with reference to this specific use. It should be
kept in mind, however, that this is done for purposes of
description, and not by way o~ limitation.
For many years, corneal contact lenses constructed
of relatively hard plastics have been in use. These lenses,
while effective, have a disadvantage in that they often pro
duce discomfort to the wearer, and thus in many instances
can only be worn for short durations. Recently, there has
been developed an extremely soft contact lens which fabrica~ed
from a pliable plastic material is thus less likely to cause
dIscomfort. These pliable plastics are quite hy~rophlic, ~ -
and accordingly are susceptible to contamination by micro~
organisms. As such, the user of these newer, softer lenses ~`
must take care to sterilize his, or her lenses daily.
A number of sterilizing techniques have been
developed, several of which utilize the heating of the lenses
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in a closed vessel, in the presence of a saline solution,
heating taking place to a sufficiently high temperature to
achieve destruction of contaminants, such as micro-organisms.
There has also been proposed, more recently, a sterilizing
process which does no~ u~ilize heating, but rather employs
an anti--microbial solution, such as for example hydrogen
peroxide (H2
With the pre~;ously employed techniques utilizing
heating, the only concern regarding safety to the wearer, was
~hat the lenses and capsule cool sufficiently. Where an
anti-microbial sterilizing agent is used, care must be taken
to insure that the solution is in someway neutralized prior ;
to insertion of the lens into the eye. If this is not done,
there is a distinct danger of damage to the eye, and at the
very least discomfort to ~he user.
There has been proposed a process of sterilization -
wherein hydrogen peroxide is employed as the anti-microbial
agent, in a relatively weak concentration, on the order of
a 3% solu~ion. As to subsequent decomposition, the sterili-
zing solution provides a reactant which when brought into
contact with a catalytic agent, such as platinum, will pro~
duce a chemical reaction resulting in neutralization or decay
o~ the hydrogen peroxide. In this regard, oxygen is liberated
and the hydrogen peroxide is reduced to water. The whole pro-
cess takes place over a period of time, depending of course
on the nature of the catalytic agent and the strength of the
original solution, but the end result is a sufficien~ly decay~
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solution which will permit the lenses to be removed and dis-
posed on ~he wearer's cornea without danger of discomfort or
damage.
Even with the above-discussed process, there are
certain safety considerations. In this regard, the initial
concentration of the sterilizing solution must be quite low,
on ~he order of three percent (3/O)o This low concentration
is employed as a safety factor in that should the user acci-
dently inser~ the lenses, prior to decomposition of the
10 hydrogen peroxide, only discomfor~ will result, rather than ;~
serious damage. A problem does exist, however, in that in
order to achieve the desired degree of sterilization, the~-
contact lenses must be subjected to a solution of adequate
strength for a sufficient durationO With the above-discussed
: process, where a catalytic agent is used to produce a decay-
ing chemical reaction, a reduction in strength of the hydrogen
peroxide commences immediately, with the solution decaying
rapidly. The overall decaying process, as a function of time
and strength of solution, is indicated generally in the dotted
portion o the graph of FIG. 9 of the drawings~ As such,
since it is not practical to employ strong solutions, and
further since decay of the hyd~ogen peroxide will start as
soon as it is brought into contact with a catalyst, there is
a distinct possibility that insufficient sterilization may
resultO
The present invention thus provides a method and~ :
apparatus for use in the sterilization of contact lenses, or
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the like, disposed within a sterlizing solution contained
wlthin a reaction vessel, which sterilizing solution iæ capa- ~ ;
ble of undergoing decomposition through contact with a cata-
lytic agent. The apparatus comprises: a housing; a timlng
mechanism disposed within said housing; and support means
rotatably mounted to the housing and adapted to receive a
vessel in a first vertically oriented position, which vessel
is adapted to contain said sterilizing solution and said cata-
lytic agen~ with said catalytlc agent out of contact with
said solution, when said vessel is in said first vertical
orientatîon. Means are employed which operatively connect
- said rotatably mounted support means with said timing mechanism,
such that upon expira~ion of a preset period of time, said sup~
port means will be rotated, thereby to place said vessel in a
second vertical orientation, with said sterilizing solution
being brought into contact with said catalytic agent to pro-
duce decomposition of said solution. As to said method, it
comprises the steps o~: providing a closed vessel partially
filled with steriliæing solution; placing the lenses in said
vessel in contact with said sterilizing solution; disposing
; said catalytic agent lnternally of said vessel; maintaining
the strength of said sterilizing solution by delaying the
decomposition reaction which will take place between said
solution and said catalytic agent. The step of delaying de-
composition including positioning of the vessel in a first
vertical orientation with said article in contact wi~h said
sterilizing solution, while the catalytic agent is disposed
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above and out of contact with said solution, and repositioning
said vessel after a prescribed period of ~ime to invert said
vessel causing the catalytic agent to contact the sterilizing
solution thereby commencing the decomposition reac~ion, and
allowing said sterilizing solution to decay to a level wherein
the strength thereof is below a specified concentrationO
A graph of the above-discussed method as a function
of time and strength of solution is shown in Figo 9 in full
line, with a one hour delay in commencement of the decaying
reac~ion being shownO
Brief Description of the Drawings
Figo 1 is a front perspective view of an inverter
mechanism cons~ructed in accordance with the present
invention;
Figo 2 is a perspective view of the rear of the
inverter mechanism illustrated in Figo 1 and shown partially
disassembled and also illustrating the holder for the con-
tact lens sterilizing capsule;
Figo 3 is a partial perspective view o~ the timing
mechanism and support arrangement for the contact lens
capsule, with a typical type of capsule shown in exploded
perspective;
~ 6~ ~
Fig. 3A is a partial sectional view through the capsule,
illustrating same in the in~erted position Erom that as shown
in Fig. 3;
Fig. 4 is a front elevational view of the timer
mechanism of Fig, 3 with the knob portion thereof removed and
certain elements broken away to illustrate ~he condition of
the acutator ring and drive mechanism when the timer has been
set to run the full cycle;
Fig. 5 is a view similar to Fig. 4 but illustrating the
condition immediately preparatory to inverting of ~he capsule;
Fig. 6 is a partial, elevational view similar ~o
.,,
Fig. 4 and illustrating the intermediate position immediately
after initiation of the inverting action;
Fig. 7 illustrates the condition once inversion has
been completed;
Fig. 8 is a schematic representation of one form of
timing mechanism that may be employed with the present invention; -
Fig. 9 is a graphic representation of a method of
. ~
;~ ~ the present invention as compared with the prior art.
20 Description of the Illustrated Embodiment ;~
The above-discussed method can be readily attained
by employment of apparatus, such as tha~ shown in Figs. 1 - 8
of the drawings and a discussion of this preferred form will
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~ now follow. It should be noted, however, that the method of
:,. : ~ '
this invention may be practiced by use of other apparatus,
which achieves the desired inverting of the capsule after a
preset period of time.
.
Turning now to the drawings, there will be had a
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detailed description of the illustrated mechanism for attaining
the desired mode of operation. A preferred fonm of inverting
unit, which is designated generally 10, is shown in Fig. 1.
The unit includes a housing 12, which as can be seen from Fig.
2 is comprised o~ upper and lower housing segments 14 and 16.
Please note that the housing 12 is of a generally L-shaped
configuration which is employed to provide a compact, stable
construction. As can be seen in Fig. 1, a timer dial 18
extends from the front face of the housing 12 on which there
may be employed indicia which are ca~librated in accordance
;~ with the internal mechanism of the tim~r to provide visual
indication of the delay period to be obtained from various
settings of the dial 18.
~' With reference to Fig. 2, the rear portion of the
j~ ,
inverting unit 10 can be seen. In this regard, there is
provided a reaction vessel or capsule 22 in which ~he
sterilizing and decaying reactions take place. The unit 10 " '
is provided with a generally U-shaped or bifUrcated support
bracket 24 into which the capsule 22 is mounted.
Initially, the timer mechanism, which will'be
,
dis~cussed hereinafter, is set by rotation of the timer dial
' 18. Said rotation wîLl automatically orient the bracket 24 ~'
~ in a generally vertical position, as will be clear from the
'~ disc'losure to follow. Next 9 the capsule 22 is prepared and
' then mounted to the bracket 24. Once'the timer mechanism has
timed out, the support bracket 24 will be rotated approximately
180 to invert the capsuLe and thereby bring the sterilizing
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solution into contact with the catalytic agent to produce the
desired decaying reaction of said solution. This condition is
shown in Fig. 3A.
Direc~ing attention to Figs. 3 and 3A there is
illustrated in Fig. 3 the basic internal mechanism of the unit
10 which achieves the desired mode of operation, and there is
also disclosed in Fig. 3A a preferred form of lens capsule. Con-
sidering first the lens capsule 22, the design thereof is gen-
erally similar to that as disclosed in U. S. Patent No. 3,770,113, ~ `., ~
issued to Michael D. Thomas, a co-inventor herein, on November
6, 1973. Basically, the capsule 22 includes a generally cylin-
drical housing 30 open at both ends. A cap element 32 is pro-
~ vided at one end, which cap element includes a lens receptacle
;~ 34 having a pair of hinge covers 36, which provide access to a -
;: :
j lens accommodating area. Initially the lenses are disposed
~; within said lens accommodating areas, and the hinge covers 36
;` are closed ~o maintain the desired positioning of the lenses.
~ It should be noted that the covers 36 are suitably apertur~d ;`
; ~ to allow the sterilizing solution to flow into contact with ~ ;~
2V the lenses. At the opposite end of the housing 30, there is
.
provided a second end cap 40 which in the illustrated form of
the invention, has the catalytic agent secured thereto. Con- ~
cerning the illustrated embodiment, the catalytic agent is in ; ~;
the form of a platinum coated plastic ring 42 affixed directly
: :
to the end cap 40.
In preparing the capsule 22 for the sterilizing
operation, the initial position as shown in Fig. 3 is used.
The contact lenses are ~irst positioned within the holder
34 and the end cap 32 is secured in place. Next, the
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sterilizing agent, preferably hyrdogen peroxide, is introduced
into the capsule 22 to a sufficient level to cover the lenses.
The cap 40 is secured in position, with the catalytic agent
42 disposed above and out of contact with the sterilizing
agent. The capsule in this orientation is then mounted to the
U-shaped bracket 24.
The U-shaped or bifurcated bracket 24 is fabricated
from a pliable plastic material, and thus is of a generally
resilient construction such that it will closely engage the
housing 30 of the capsule 22 with a snap-fit type of action.
That is to say, that the degree of engagement is such that
the capsule will be held firmly in position~ but can be
manually removed.
Directing attention to the left hand portion o~
Fig. 3, it should be noted that the U-shaped supporting bracket
24 is mounted on the end o~ a shaft 44 which is in turn
rotatably mounted or journaled to a support plate 46. Also
~ on the support plate 46, is a timer mechanism 47 which will -
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~ be discussed in greater detail hereinafter. The end of the ~
.. . . .
20 shaft 44 opposite the bracket 24 includes the gear element ~
: . . .
48; In general alignment with the gear element 48 is a
rotatably mounted disc element 52 which includes a series of
gear teeth 50 formed thereon, which teeth are adapted ~or ~-
meshing engagement with the gear member 48 ~or purposes to ~ ;
be de~ailed hereina~ter.
Returning briefly to Fig. 2, it should be noted
that the upper and lower housing segments 12 and 14 are
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provided with semi-circular recesses 54 and 56 which accommo~
date the shaft 44 and enable i~ to protrude outwardly thereof.
The opposite side of the housing is correspondingly provided
with semi circular recesses of sufficient size to accommodate
the timer dial 18. Interiorly of the respective housing
elements 14 and 16, there is provided groove means (not shown)
into which ~he edges of the support plate 46 are received, ;~
thereby serving to hold said plate 46 in proper position =~
interiorly of the housing 12. Also, it should be noted that '
in Fig. 2, the capsule 22 is illustrated in the inverted
positlon, that is, after the sterilizing solution has been
: : .
brought into contact with the catalytic agent.
To review briefly, the operation of the device 10
involves initial presetting of the timer 47 to the desired
period for delay. Thereafter, the prepared capsule 22, in
the general orientation as shown in Fig. 3, is engaged with
thes~1pport bracket 24. The timer is then allowed to run its
program duration and at expiration of the preset period, -~
rapid movement of the disc element 52 will be effected through
a relatively small arc, bringing the gear teeth 50 on said ~
disc 52 into meshing contact with the gear member 48 and thus ~;
producing rotating of shaft 44, and the support 24, along with
the associated capsule 22. This rotation of the capsule 22
is through 180 and will effect inverting of said capsule to `~
a positlon as shown in Figs. 2 and 3A; thereby placing the cap 40
with the catalytic agent 42 in the lowermost position so as
to bring the sterilizing so~tion 41into contact with the catalytic
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agent 42~ The catalytic agent 42 wilL react with the sterili-
zing agent (hydrogen peroxide) to commence the decaying action
which after a period of six hours, or so, will reduce the a
hydrogen peroxide to water thereby rendering the lenses
safe for insertion in the eyes of the user, without danger of
discomfort or damage.
The specific mechanism of the device 10 which
achieves the above-discussed operation and ;nverting of the
capsule 22, will now be considered in detail. Attention
is first invited to Fig. 89 where there is illustrated,
somewhat schematically~ one form of timing mechanism 47.
The mechanism illustrated is of a generally standard design ~-
and of a type adapted to derive its motive power from a
coiled main spring. As such~ the device 10 can operate inde-
pendently of an~ electrical outlet. Of course, it is to
be understood that the arrangement 47 to be discussed herein-
after is illustrative of one form of timing mech~$m that
can be used, with the specific description thereof being
included for purpose of providing a complete disclosure of a
preferred form of the invention. It is understood, and in
fact contemplated, that those skilled in the art, when ~
equipped with the knowledge provided by the present disclosure, ~ ~-
may devise or adopt other modes or forms of timing mechanisms,
as well as aLternate arrangements for operatively coupling
the timing mechanism to the journaled shat 44. With this
in mind, specific consideration is directed to the arrangement -
as shown in Fig. 8.
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Specifically, ~he timer mechanism 47 includes a
central or main shaft 60 to which is mounted a main gear
element 62. A coiled main spring member 64 is operatively
engaged wikh the shaft 62 tending to bias said shaft in a
coun~r-~ockwise direction. Through a reduction gear train, ~ -
comprised of gears 66, 67, 68, 69, 70, 71, 72 and 73, the main
gear 62 is operatively connected to an escapement device 74.
The escapement device 74 includes a pivotally mounted arm 76
and a pair of escapement pins 78 and 80 which are engaged
10 alternately with the gear 73 to permit only incremental ;
;movement of said gear. In this regard it will be apprecia~ed
that the embodiment is generally conventional in design, with
the main spring 64 tending to produce rotation, and the
escapement mechanism 74 allowing only incremental movement
o the gear members. The gear reduction provided by the
gear train 66 - 73 providing for the desired rate of movement
of the main shaft 60. It should be noted further, that at
a location designated generally 82, a section of the gear
teekh on the gear 62 have been removed, for a purpose which
20 will be explained hereinafter. ~`
The orientation of the elements as shown in Fig.
8 illustrate the condition of the timing mechansim 47 upon
initial setting thereof. Accordingly, as the timing mechanism
47 times out, the main gear 62 will move in a counter-clockwise
direction as indicated by the arrow 84~ As the main gear 62
rotates, eventually the counter-clockwise movement will bring
the smooth section into confronting relation with the gear 66.
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When this occurs, the main gear 62 will no longer be operatively
engaged with ~he escape mechanism 74 through the gear train
66 - 73, and therefore wîll be free of the retarding action of
said escapement mechanism. Accordingly, keeping in mind the
biasing action of the spring 64, the main gear 62 and shaft
60 will then rotate rapidly through an arc approximately
equal to the extent of ~he smooth, gear tooth-free section 82.
With reference to the previous discussion, it
should be noted that the rotary disc 52 having the gear teeth
10 50 thereon is also mounted to the main shaft 60. The rapid
rotation of said shaft 60 mentioned in the preceding paragraph
will thus provide the necessary rotative movemen~ required
to bring the gear teeth 5G into meshing engagement with the
gear element 48 and correspondingly produce the inverting
~ ~ rotation of the shaft 44 and the support bracket 24 mounted
; on one end thereof.
~: .
In Figs. 4 ~ 7, there is illustrated the sequential ; ~
;~ ~ relationship between the rotary disc element 52 and the gear ; ~ `
mem~er 48, during opQra~ion of the device 10 under the
20 influence of the timing mechanism 47 as previously dis~ussed.
In addition, Figs. 4 - 7 also illustrate a preferred form of
positioning means which is employed to maintain the desired
orientation of the bracket 24 so that the capsule 22 is in <
proper position for the delay period, i.e. wherein the contact ; ~
lenses will be subjected to the hydrogen peroxide at elevated ~ ~ ;
strength, prior to commencement of the decaying action upon
initial contact of said solution with the catalytic agent 42.
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Considering first Fig. 4, the rotary disc 52 is
shown partially broken away to expose to view a positioning
ring segment 90 which is affixed to and moves with ~he disc
element 52, the purpose of which will be detailed hereinafter.
Rotary disc 52, as mentioned above, is mounted to the main
shaft 60 of the timer mechanism 47 as is the timer dial 18.
Said disc 52 includes a pair o oppositely disposed stop ~
members 92 and 94 on the periphery thereof. Also visible in ;
Figs. 3 and 4, are a pair of radially disposed abutment
10 flanges 96 and 98 formed on the gear member 48. Immediately
- behind the gear member 48 and spaced slightly rearward of the
rotary disc member 52 there is provided a cam-like element 100
which includes a convex surface portion 102. `
Accordingly, when the timer mechanism 47 is set, the ;
dial 18 is rotated in a clockwise direction to produce corres-
ponding rotation of the main shaft 60 which in turn winds the
main spring 62. The clockwise rotation of the dial 18 is
limited by engagement of the stop member 94 with the abutment
flange 96 on the gear member 48, as shown. This is then the
maximum setting ~or the timer.
In addition, the clockwise movement of the dial 18
:
: and the disc 52 will bring the ring segment 90 to an orientation
as shown in Fig. 4. In this position9 the arcuate surfa~e of
the ring segment 90 will be in opposed abutting contact with
the concave surface 102 on the ~ ement 100. As such, engage-
ment between the respecti~e opposed surfaces wiLl preclude
,~ ~
rotation of the element 100, and since that element 100 is
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affixed to shaft 449 this engagement also serves to ~ix the
position of ~he support 24 in the desired vertical orientation.
Thus, it can be seen that once the timer 47 is set and the
capsule is engaged with the support bracket 24, the orientation
of the capsule 22 is fixed. A discussion of the manner in
which the shaft 44 is freed for rotation and the manner in ;~
which said rotation is achieved follows.
With Fig. 4 as a starting point, as the timer
mechanism 47 ~imes out, the shaft 60 and correspondingly
disc 52 will move in a counter-clockwise direction. Eventually,
the continuous, incremental movement allowed by the timing
mechanism 47 will proceed until the condition as shown in
Fig. 5 is reached, wherein the gear tooth section 50 on ring
52 is disposed proximate the gear member 48. With reference
to the discussion of the ooeration of the timing mechanism
of Fig. 8, it should be noted that at this point in the `
operation of dPvice 10, the smooth, toothless portion 82 of
the main-gear 62 will have moved into opposed position relative
to the gear 66, so that the retarding effect of the escapement
.
mechanism 74 on the main gear 62 is interrupted. As such,
the gear 62 wi~l rotate rapidly through a small arc, as dis~
cussed above, producing corresponding rotation of shaft 60
and disc element 52, as indicated by the arrow 104. This
rotation of the disc 52 will bring the gear teeth 50 into
meshing engagement with the gear member 48, quite rapidly,
as shown in Fig~ 6, to produce rotation of the gear element
48 to the position as shown in Fig. 7. In this regard, with
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reference to the datum arrow 106, it can be seen that the
orientation of the shaft 44 to which the gear element 48 is
affixed, has been changed, approximately 180.
As an additional point, with reference back to Fig.
5, it should be noted that just prior to engagement of the
gear member 48 by the gear teeth 50, the ring segment 90,
which is affixed to the rotating disc elem~nt 52 will have
been moved out of engagement with the concave surface 102.
This action, thus frees the shaft 44 and the gear member 48
to rotate upon the subsequent engagement o~ the gear teeth 50
wh;ch will take place immediately thereafter. ~-~
~ Considering Fig. 7 again, it will be noted that by
~ reference to the datum arrow 106, the gear element 48 has been
rotated approximately lS0. Thus, as discussed above, thPre is
~- achieved orresponding rotation of the shaft 44 to achieve ~ -
: inverting of the capsule 22. As the ring segm~-t 90 has been
moved past the area of the cam-like element 100, the convex ~ -
portion of said element 100 is free to pass radially i~wardly
of, and behind, the periphery of the disc member 52.
~ 20 - Rotation of the ring 52 in the counter-clockwise
:~ dir~ction is limited by engagement of the stop 92 with the
~ ~ .
. abutment 108, as seen in Fig. 7. Also, the above-mentioned
rotation o~ the gear element 48 will bring the abutment flange ~;
into engagement with the periphery of the disc 52. Both of .
:
these instances o~ engagement serve to absorb any s-train that . .
:~ may be placed on the device by an attempt to further rotate
: the support bracket 2~ in a clockwise direction. That is to
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say, any such movement will be precluded by the respective
abutments and thus will not be applied to the gear element
in such a manner as to produce damage ~hereto.
An addi~ional factor which should be noted, is the
fact that in the position as illustrated in Fig. 7 the gear
teeth 50 remain in driving engagement with the gear member
48. Accordingly, assuming resetting of the device 10, when
the dial 18 is rotated in a clockwise direction, as indicated
by the arrow 110, the gear 48 will also be rotated back toward
the position as shown in Fig. 5, and the positioning ring
~ .
segment 90 will be re-engaged with the concave surface 102.
The net effect of this action, is to insure proper orientation
: ~ -
of the bracket 22 upon resetting of the timer 47 In this
regard, once the bracket achieves a vertical orienta~ion,
similar to that as indicated by the datum arrow 106, the j~-
meshing engagement between the gear 48 and the gear teeth 50 ~ ;
will be interrupted, and rotation of ~he ring 52 in a clock-
wise direction to achieve setting of the timer can take place, `~
~ with the elements affixed to shaft 48 properly positioned to
-~ 20 achieve vertical orientation of the bracket 22.
Fig. 9, which was alluded to previously, provides
a graphic representation of the method of the present invention
vis-a-vis the conventional steriliæing process wherein the
catalytic agent is brought into contact with the sterilizing
solution immediately. In this regard, Fig. 9 is a repre-
sentation of strength of solution, as opposed to time. The
graph 112 in dotted line represents the convention process,
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while the graph ll4, in solid line is representative of the
process of the present invention, wherein a delay in the
decaying or neutraLizing reaction is produced. It should be
noted that the graphs 112 and 114 are generally illustrative
of the respective process, and no r~presentation as to the
exact accuracy of the slope of the curve is noted.
While the present invention has been described
and illustrated in conjunction with a preferred embodiment~
it is to be understood that it is not intended to limit said
invention thereto. Applicants can foresee, and indeed would
expect those skilled in the art and equipped with the present
disclosure to devise various modifications, alterations,
or substitutions for the specific apparatus and procedural
steps described`and illustrated. As such, it is Applicants'
~` intent to cover any and all modifications, alterations, etc.
falling within the spirit and scope of the invention, as
;~ expressed by the claims appended hereto, in accordance with
the patent laws. ~
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